KANSAS CITY, Mo. (AP) — A fire official says about 10 people were sickened by a suspicious package in the mailroom of a sprawling IRS building in downtown Kansas City, Missouri. 
 
 Kansas City Fire Department spokesman James Garrett says 10 people complained of feeling ill, including vomiting and sweating, after the package arrived at the building Friday. He says two people were taken to a hospital. 
 
 St. Luke's Hospital spokeswoman Laurel Gifford says those victims are in good condition. 
 
 Garrett says the Fire Department was checking for gasses and fumes but hasn't determined the package's contents. He says the package was isolated from the public. 
 
 The building was not evacuated and has returned to business. 
 
 Garrett says the investigation has been turned over to the IRS and other federal authorities. ||||| New York (CNN) A suspicious package addressed to actor-director Robert De Niro was reported early Thursday at the Manhattan building where his production company is based, and its marking and contents appear similar to pipe bomb packages recently mailed nationwide to top Democrats, two law enforcement sources said. 
 
 Also Thursday, two suspicious packages addressed to former Vice President Joe Biden were found in Delaware , law enforcement officials said. 
 
 A photo of the package sent to Robert DeNiro, provided by a law enforcement official. 
 
 With Thursday's discoveries, at least 10 suspicious packages, all similar in appearance, have been found this week addressed to eight people who are prominent Democrats or high-profile critics of Donald Trump. 
 
 The package addressed to De Niro, found on the seventh floor of 375 Greenwich St. in New York City's Tribeca neighborhood, was reported to police around 4:45 a.m. 
 
 The building contains Tribeca Enterprises -- which includes De Niro's Tribeca Productions film and television company and organizes the Tribeca Film Festival -- and De Niro's Tribeca Grill restaurant 
 
 The package was received in the building's general mailroom on Wednesday, according to a law enforcement official. A retired police officer discovered the package, but initially didn't think anything of it and left it in his office. 
 
 After watching news reports, he recognized similarities between the package he had seen and the others sent to top Democrats and CNN, the official said. He called police early Thursday morning to inform them about it. 
 
 Police have sent the package to a secure facility in the Bronx, New York Police Department Commissioner James O'Neill said on Twitter 
 
 "The most highly trained experts in the world are investigating today's suspicious package in #TriBeCa," O'Neill's tweet reads. 
 
 X-ray images show that the package addressed to De Niro contains a device similar to the pipe bombs found in other packages this week that were addressed to prominent Democrats, the two sources said. 
 
 De Niro is a vocal critic of Trump. 
 
 JUST WATCHED Bombs sent to politicians in 'act of terror' Replay More Videos ... MUST WATCH Bombs sent to politicians in 'act of terror' 02:33 
 
 The package sent to the actor also had the same return address as the others: that of Democratic US Rep. Debbie Wasserman Schultz of Florida, the sources said. There is no information to suggest she sent the packages. 
 
 And, just as the other packages, the one sent to De Niro had six American-flag stamps arrayed in two rows. No postmark is visible on the front of the De Niro package, similar to some of the others, the sources said. 
 
 None of the bombs in the other packages detonated, and no one was injured. 
 
 JUST WATCHED X-ray of package reveals new info Replay More Videos ... MUST WATCH X-ray of package reveals new info 01:32 
 
 Before the De Niro and Biden packages were in police custody Thursday, authorities said seven pipe bombs stashed in manila envelopes were discovered this week addressed to six prominent Trump critics: Former President Barack Obama; former Secretary of State Hillary Clinton; former Attorney General Eric Holder; Democratic US Rep. Maxine Waters (one to her California office and one to her office in Washington); former CIA director John Brennan (sent to CNN's New York offices); and billionaire investor and Democratic donor George Soros. 
 
 Most of those devices showed the presence of a sulfur substance , which could have exploded, a law enforcement official said. 
 
 Those devices are believed to be pipe bombs, inherently unstable, and at risk of being set off just by handling. 
 
 Authorities already were aware at least one Biden package by Wednesday; it had been misaddressed and returned to sender, and postal officials were trying to track it down, two law enforcement sources said. 
 
 This photo of the package addressed to Biden was obtained by WTFX-TV in Philadelphia. 
 
 Details about how authorities ultimately found the two Biden packages on Thursday morning in Delaware weren't immediately available. But Delaware authorities have said investigators have responded to post offices in Wilmington and New Castle. 
 
 The FBI said Thursday that the package addressed to De Niro and the two addressed to Biden were "similar in appearance to the others." 
 
 The #FBI has confirmed three additional packages, similar in appearance to the others -- one in New York addressed to Robert DeNiro, and two in Delaware addressed to former Vice President Joseph Biden. — FBI (@FBI) October 25, 2018 
 
 Building is open after evacuation 
 
 Tribeca Enterprises co-founder Jane Rosenthal said Thursday that the building was evacuated after the package was found, but that it has been re-opened. 
 
 "The building is open and everybody is safe," she told CNN. "This is not what free speech should look like." 
 
 A police officer blocks off an area in Manhattan Thursday morning after a suspicious package addressed to Robert De Niro was reported at the Tribeca Enterprises building. 
 
 De Niro's criticism of Trump 
 
 At June's Tony Awards, De Niro went off-script while introducing a performance by Bruce Springsteen to curse Trump. 
 
 "First, I wanna say, 'f**k Trump,'" De Niro said. "It's no longer 'Down with Trump,' it's 'f**k Trump.'" 
 
 Trump responded to the comments in a series of tweets, calling De Niro "a very low IQ individual." 
 
 JUST WATCHED De Niro apologizes to Canada for Trump Replay More Videos ... MUST WATCH De Niro apologizes to Canada for Trump 00:46 
 
 It wasn't the first time De Niro had spoken out against the President. 
 
 In January, his speech at the National Board of Review Annual Awards Gala included a profanity-laced rant directed at Trump. 
 
 "Our baby-in-chief -- the j***-off-in-chief, I call him -- has put the press under siege, ridiculing it and trying to discredit it through outrageous attacks and lies," De Niro said. ""This f***ing idiot is the President. It's 'The Emperor's New Clothes' -- the guy is a f***ing fool ... our baby-in-chief -- the 'J******-in-chief' I call him." ||||| James Holmes, the accused gunman in last Friday's midnight movie massacre in Colorado, mailed a notebook "full of details about how he was going to kill people" to a University of Colorado psychiatrist before the attack, and the parcel may have sat unopened in a mailroom for up to a week before its discovery Monday, a law enforcement source told FoxNews.com. 
 
 "Inside the package was a notebook full of details about how he was going to kill people," the source told FoxNews.com. "There were drawings of what he was going to do in it -- drawings and illustrations of the massacre." 
 
 Among the images shown in the spiral-bound notebook’s pages were gun-wielding stick figures blowing away other stick figures. 
 
 The source said police and FBI agents were called to the University of Colorado Anschutz medical campus in Aurora on Monday morning after the psychiatrist, who is also a professor at the school, reported receiving a package believed to be from the suspect. Although that package turned out to be from someone else and harmless, a search of the Campus Services' mailroom turned up another package sent to the psychiatrist with Holmes’ name in the return address, the source told FoxNews.com. 
 
 A second law enforcement source said authorities got a warrant from a county judge and took the package away Monday night. When it was opened, its chilling contents were revealed. 
 
 The first source on Tuesday told FoxNews.com the package had been in the mailroom since July 12, though another source who confirmed the discovery to FoxNews.com could not say if the package arrived prior to Friday's massacre. It was not clear why it had not been delivered to the psychiatrist. 
 
 The notebook is now in possession of the FBI, sources told FoxNews.com. 
 
 The University of Colorado Denver issued a statement Wednesday evening confirming that a suspicious package was found, but called the July 12 timeline "inaccurate." The university said it was delivered Monday and found on the same day. 
 
 When told of the university's statement, a source said the package may have been postmarked on July 12, but arrived before the massacre. 
 
 On Tuesday afternoon, in response to FoxNews.com’s request for comment prior to publication of this article, the same university spokeswoman, Jacque Montgomery, had said only that she was not aware of the contents of the package or who had sent it. 
 
 The university also denied Wednesday that the package "sat on a loading dock," though there was no mention of a loading dock in the original FoxNews.com story. The story reported the package was instead found in a mailroom. 
 
 Both of FoxNews.com's sources said the intended recipient of Holmes’ notebook was a professor who also treated patients at the psychiatry outpatient facility, located in Building 500, where the first suspicious package was delivered. It could not be verified that the psychiatrist had had previous contact with Holmes, who was a dropout from the school’s neuroscience doctoral program and had studied various mental health issues and ailments as part of his curriculum. 
 
 Holmes is accused of killing 12 and injuring 58 at a midnight showing of the Batman movie "The Dark Knight Rises" at the Century 16 Theater in Aurora. 
 
 Agent Dave Joly, of the FBI’s Denver Division, declined to comment on the matter, citing a gag order issued Monday by Arapahoe County District Judge William Sylvester. Arapahoe County District Attorney Carol Chambers' office and Aurora police also could not comment due to the gag order. 
 
 Police believe the July 20 attack was meticulously planned. Holmes allegedly tossed tear gas canisters into the crowded theater, and then fired his 12-gauge shotgun at the ceiling before turning it on the crowd. As panicked movie watchers raced for the exits, he switched to a .40 Glock pistol and a .223 Smith & Wesson M&P semi-automatic with a high-capacity drum clip, sources told Fox News. The gun jammed, likely preventing far more deaths. 
 
 After the gun jammed, Holmes allegedly walked out of the theater through the door he'd entered and was removing his body armor beside his car when he was confronted by the officers who took him down, the source said, adding that the gunman seemed surprised authorities arrived so quickly. 
 
 Before mounting the horrific attack, Holmes allegedly booby-trapped his apartment and left music blasting, possibly to create a diversion that would occupy police and rescue personnel several miles away from the theater, the source said. 
 
 Fox News has learned that the door was wired with a booby-trap and a backup system that would have triggered an explosive designed to "cut in half" the first person through the door. After that, explosions and flames would have likely consumed the entire building, presumably with the intention of trapping other residents as they slept and forcing a massive response of police and rescue personnel. 
 
 Holmes, who made his first court appearance Monday and looked disoriented and disheveled, could face the death penalty. 
 
 Editor's Note: This story was updated Wednesday evening to include a statement from the University of Colorado Denver, and a response to that statement from a FoxNews.com source. 
 
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– About 10 people were sickened after a suspicious package arrived in the mailroom of an IRS building in Kansas City, Missouri, Friday morning, a fire official tells the AP. Symptoms included vomiting and sweating; two of the people were taken to a hospital but are in good condition. The package's contents have not yet been determined, but the fire department is checking for gasses and fumes. The building was not evacuated, but the package has been isolated from the public. Law enforcement is investigating, the Kansas City Star reports.