U.S. & World

FORT HOOD, Texas (CBS) ― A soldier opened fire at a U.S. Army base in Fort Hood, Texas on Thursday, unleashing a stream of gunfire that left 12 people dead and 31 wounded. Authorities shot and wounded the gunman, and apprehended two other soldiers suspected in what appears to be the worst mass shooting at a U.S. military base.

The military identified the shooter as Major Nidal Malik Hasan, 39, a psychiatrist.

The shooting began around 1:30 p.m., Lt. Gen. Bob Cone said at a news conference. He said all the casualties took place at the base's Soldier Readiness Center, where soldiers who are about to be deployed or who are returning undergo medical screening.

"It's a terrible tragedy. It's stunning," Cone said.

Hasan used two handguns in the attack, Cone said. It was not clear if he stopped to reload.

Hasan has been hospitalized, Cone said, but would not say what the soldier's condition was.

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The official says investigators are trying to determine if Hasan was his birth name, or if he changed his name and converted to Islam at some point in his life. Investigators were trying to determine a motive for the shooting.

The post was immediately put on lockdown, but that state of emergency ended just after 7 p.m. when the post was reopened, CBS station KTVT-TV reported.

Two other soldiers taken into custody following the deadly rampage were later released, the office of a Texas congressman said. A spokesman for Rep. John Carter says Fort Hood officials informed Carter's office of the release. Carter's congressional district includes the Army base.

A Fort Hood spokesman could not confirm that the two had been released.

A graduation ceremony for soldiers who finished college courses while deployed was going on in an auditorium at the Readiness Center at the time of the shooting, said Sgt. Rebekah Lampam, a Fort Hood spokeswoman.

Greg Schanepp, U.S. Rep. John Carter's regional director in Texas, was representing Carter at the graduation, said John Stone, a spokesman for Carter, whose district includes the Army post.

Schanepp was at the ceremony when a soldier who had been shot in the back came running toward him and alerted him of the shooting, Stone said. The soldier told Schanepp not to go in the direction of the shooter, he said. Stone said he believes Schanepp was in the theater.

The wounded were dispersed among hospitals in central Texas, Cone said.

The shootings on the Texas military base stirred memories of other recent mass shootings in the United States, including 13 dead at a New York immigrant center in March, 10 killed during a gunman's rampage across Alabama in March and 32 killed in the deadliest mass shooting in modern U.S. history at Virginia Tech in 2007.

Around the country, some bases stepped up security precautions, but no others were locked down.

"The bottom line for us is that we are increasing security at our gates because the threat hasn't yet been defined, and we're reminding our Marines to be vigilant in their areas of responsibility," said Capt. Rob Dolan, public affairs officer for the Marine Corps Air Station in Yuma, Ariz.

In Washington, President Barack Obama called the shooting "a horrific outburst of violence." He said it's a tragedy to lose a soldier overseas and even more horrifying when they come under fire at an Army base on American soil.

"We will make sure that we get answers to every single question about this horrible incident," the commander in chief said. "We are going to stay on this."

Covering 339 square miles, Fort Hood is the largest active duty armored post in the United States. Home to about 52,000 troops as of earlier this year, the sprawling base is located halfway between Austin and Waco.

About a mile from Fort Hood's east gate, Cynthia Thomas, director of Under the Hood Cafe, a local coffee shop and nonprofit military support center, has been calling soldiers and friends on the post to make sure they're OK.

"It's chaotic," Thomas said, as a SWAT team just drove by. "They're just saying that they're under attack they don't know what's going on. ... The phones are jammed. Everybody is calling family members and friends. Soldiers are running around with M-16s."

Fort Hood officially opened on Sept. 18, 1942, and was named in honor of Gen. John Bell Hood. It has been continuously used for armored training and is charged with maintaining readiness for combat missions.

(© 2009 CBS Broadcasting Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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