President Barack Obama has called a mass shooting at a US base in which at least 13 people were killed and 31 wounded a "horrific outburst of violence". Skip related content
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At least 12 dead in US military base shooting
The attack happened at the Soldier Readiness Center at Fort Hood in Texas.
Reports suggest that the main gunman has been wounded and remains in a stable condition.
Speaking on CNN, Lieutenant General Russel Honore, a former commander general at the Fort Hood compound, said he had been told that two men, armed with M16 rifles, carried out the attack:
"One was neutralised and the other was cornered," he said.
Fort Hood is a sprawling 340 square mile military installation, the largest in the world, situated 50 miles south of Waco and a prime point of deployment for U.S. operations in Iraq and Afghanistan.
It houses some 5,000 active duty officers and 45,000 enlisted members of the army.
The base is on lockdown, as are two nearby school districts.
Army personnel said they were not sure if the victims were civilians or military personnel.
The base has seen other violence in recent years. In Sept 2008, a 21-year-old soldier shot his lieutenant dead and then killed himself.
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