(CNN) -- Authorities plan to ask new questions of the family at the center of the balloon drama that captured the world's attention Thursday, as a comment in a CNN interview and other concerns raised speculation that the incident may have been staged.



Parents Mayumi and Richard Heene discuss the upheaval in their lives Friday on CNN's "American Morning."



"We feel it's incumbent on us as an agency to attempt to re-interview them and establish whether this is in fact a hoax or actual event," Larimer County Sheriff James Alderden said at a news conference Friday. "We believe at this time that it's a real event."



Investigators with expertise in spotting deceptive behavior interviewed the family Thursday and believe they were not lying, Alderden said.



His office is being flooded with calls and messages from people insisting it must be, and putting "a lot of pressure" on authorities to charge Richard and Mayumi Heene, he said.



The sheriff's office said it was conducting background checks on the Heenes.



A giant Mylar balloon took off from the backyard of the Heenes' northern Colorado home Thursday. The couple said they were terrified their 6-year-old son Falcon may have been on it. They couldn't find him.



In audio from 911 calls released Friday, the parents sounded emotional and desperate.



When the balloon finally landed, Falcon was not on board. Later, he came out from hiding in an attic over the home's garage.



"I'm feeling very, very grateful that Falcon is among us," Richard Heene told CNN's "American Morning" on Friday. "We went through so many emotions yesterday."



On CNN's "Larry King Live" Thursday night, the Heene parents asked Falcon why he had not come out from hiding when they were calling for him. "You guys said we did this for the show," he said.  Watch the boy's remarks »



The family chases storms and takes videos of some. The Heenes also were featured in March on the ABC program "Wife Swap."



After the Hollywood gossip Web site TMZ.com reported that the Heenes had been "pitching a reality show about the wacky family," one of the networks mentioned, TLC, which produces "Jon and Kate plus 8," said "they approached us months ago, and we passed."



Two other production companies, Reality Real and RDF, which produces "Wife Swap," did not immediately respond to CNN's queries.



They family had a video camera recording as the balloon took off Thursday. Alderden said that was because the family planned an experiment in which the balloon was to rise 20 feet off the ground.



Richard Heene said his son was confused when he made the show remark. There were media assembled on the front lawn, asking all sorts of questions, and that's what Falcon was referring to, Heene said Friday morning.



Heene, a meteorologist who takes his family along to chase storms, said he was concerned when the balloon took off because "the project was pretty much down the tubes." Then their son Bradford said he thought Falcon was inside, sparking the family's terror -- and the world's response, as people tuned in to live TV coverage of the balloon, which looked like a cross between a mushroom and a flying saucer.



Alderden told CNN's Wolf Blitzer on Friday that, based on reports that the parents "took these children into potentially dangerous situations" with tornado chases, the experimental balloons and other activities, it would be "appropriate to involve child protection [services] to at least see what the family situation is and whether the children are in a safe condition."



Earlier, Alderden told reporters that his department has contacted the child protection officials but asked them not to contact the family until investigators have had a chance to re-interview them.



Alderden, at Friday's news conference, said he did not believe Falcon could have been following instructions by going into hiding. "I just can't see this particular boy being told go sit up
What does the boy say? What did the sheriff say about it? What does the boy say about the stunt?
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