At least four people were killed and 14 injured in a shooting Wednesday at Fort Hood, the same base that was the scene of the worst attack on a domestic U.S. military installation five years ago, a congressman confirmed.
U.S. Rep. Michael McCaul of Texas confirmed the deaths to and said the shooter, a soldier, was among the dead.
A U.S. law enforcement official told The Associated Press that the suspected gunman is dead of what appears to be a self-inflicted wound. The official spoke on the condition of anonymity because the investigation is still ongoing.
"We're heartbroken something like this might have happened again,'' President Obama said in Chicago, after being briefed on the events.
McCaul told reporters that the suspected shooter is a soldier, Spc. Ivan Lopez.
Fort Hood confirmed the shooting on the base in a brief statement Wednesday evening. The base's official Twitter account advised all personnel on base to "shelter in place."
Fort Hood said in a statement that its Directorate of Emergency Services had an initial report that the shooter was dead, but that the report was unconfirmed.
The Army said on its official Twitter feed that the base remained on lockdown, and that injured personnel were being treated at the post's Carl R. Darnall Medical Center and other local hospitals.
Fort Hood was the base where 13 died and more than 30 were wounded in the deadliest domestic military attack in U.S. history.
Army psychiatrist Nidal Hasan was convicted and sentenced to death last year in the Nov. 5, 2009, attack on his fellow soldiers as they waited inside a crowded building at Fort Hood. Soldiers there were waiting to get vaccines and routine paperwork after recently returning from deployments or while preparing to go to Afghanistan and Iraq.
Defense Secretary Chuck Hagel, speaking to reporters while in Honolulu to host a conference of Southeast Asian defense leaders, called the shootings a "terrible tragedy." Asked about security improvements in the wake of other shootings at U.S. military bases, Hagel said, "Obviously when we have these kinds of tragedies on our bases, something's not working."