Fort Hood, Texas (CNN) -- Thirteen flag-draped coffins left Fort Hood on Friday as authorities searched for a motive in the massacre that left more than 50 casualties at the largest U.S. military base.



Thursday's mass shooting killed 12 soldiers and one civilian and wounded 38 people at the Fort Hood Army Post in Texas. The suspect in the shooting, Maj. Nidal Malik Hasan, a licensed Army psychiatrist, was among the two dozen who remained hospitalized Friday night.



Hasan was transported to Brooke Army Medical Center in San Antonio, Texas, and was in critical condition but stable, a spokesman said. Investigators were waiting to speak to the comatose Hasan, who is under heavy guard, said Col. John Rossi, the post's deputy commander.



The bodies of the 13 personnel who died were transported through a "ramp ceremony" to Dover Air Force Base in Delaware for a dignified transfer, he said. It was a "truly moving ceremony."



FBI agents helping investigate the shootings searched Hasan's apartment on Friday while investigators sifted through the crime scene, Fort Hood's military processing center, where soldiers report before they go to war.



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Hasan, who worked at a hospital on the base, is accused of using two handguns in the shooting. Two law enforcement sources told CNN that one of the weapons used is an FN 5.7-millimeter pistol, a semiautomatic purchased legally at Guns Galore, a Killeen gun shop. Details on the other gun, identified only as a type of revolver, were not immediately available.



Rossi told reporters late Friday that both guns were privately owned and never registered at the post.



Earlier, officials said investigators were looking into whether some soldiers may have been shot accidentally by others trying to shoot the gunman. However, Rossi said, "All indications are that this is not a friendly fire incident. And, of course, that will be validated when the investigation is complete."



Rossi attributed the high casualty rate to the "more than 100 rounds" fired by the gunman and the relatively small size of the room, among other factors.



Fort Hood Police Sgt. Kimberly Munley, who has been credited with shooting Hasan and ending the massacre, was among the wounded. She was in stable condition Friday night, according to her family and military officials. Munley's partner, Senior Sgt. Mark Todd, was also lauded for "engaging" the shooter, Rossi said.



Todd, in an interview Friday night with CNN's Anderson Cooper, described the intense scene as both officers fired shots at the accused gunman.



"He looked like he was calm. He was just pointing a finger at me," Todd said. "The weapon ... I just know I saw the weapon and that's when we returned fire."



Todd, a retired member of the military police, offered his condolences to the families of the victims. "I wish we could've gotten there sooner and helped out a lot sooner -- but we got there as soon as we possibly could."



Texas Gov. Rick Perry was scheduled to visit hospitalized victims of the shooting Saturday.



As the Fort Hood community grieved its numerous losses, holding a candlelight vigil and setting up support lines, some details about the alleged gunman emerged. Relatives say Hasan, a U.S.-born citizen of Palestinian descent, was a "calm" individual who had been taunted after the terrorist attacks of September 11, 2001. Others described him as a vocal opponent to the war on terror whose rhetoric concerned colleagues.



Fort Hood's commanding general said witnesses have reported that the gunman yelled "Allahu Akbar," Arabic for "God is great," during the rampage. However, Lt. Gen. Robert Cone said investigators had not confirmed that.



Hasan's neighbors at his Killeen, Texas, apartment complex said he cleaned out his place just hours before the rampage and gave copies of the Quran to several residents.



President Obama, in remarks Friday morning, cautioned against "jumping to conclusions" about what had triggered "one of the worst mass
When will be the special investigation on the shootings shown on CNN? Which residents say suspect gave them Qurans? What did the suspect do? Where was the vigil held? Who holds candlelight vigil for victims of shooting? What channel is the programme on?
Friday Hasan's neighbors at his Killeen, Texas, apartment complex killed 12 soldiers and one civilian and wounded 38 people Fort Hood Fort Hood community CNN
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