Two U.S. law enforcement officials tell The Associated Press that four people have been killed in a shooting at Fort Hood.

The officials said the four dead in Wednesday's shooting include the shooter.

One of the officials, citing official internal Justice Department updates, says 14 others were hurt.

The officials spoke on condition of anonymity because they were not authorized to release information by name.

The Texas Army base was the scene of a mass shooting in 2009. Thirteen people were killed and more than 30 wounded in what was the deadliest attack on a domestic military installation in history.

President Barack Obama says he's following the situation closely. Obama says the incident brings back painful memories of the 2009 shooting. He says, "We're heartbroken that something like this might've happened again."

Obama says people at Ford Hood have sacrificed so much for freedom and their sense of safety has been broken once again.

Defense Secretary Chuck Hagel is calling the incident a "terrible tragedy."

In remarks to reporters in Honolulu, Hagel says he is aware of casualties at the Army base in Texas and that the facility remains under lockdown.

Asked about security improvements in the aftermath of other shootings at military bases, Hagel said "something's not working" when such tragedies take place.

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