US President Barack Obama has praised the people who ended Thursday's shooting spree at an Army post in Texas, calling them heroes.
The president has promised a thorough investigation of the violence which left thirteen people dead and 38 others wounded.
He called the violence at Fort Hood heartbreaking, especially since it was perpetrated at an army post where patriots were the victims.
In his weekly Internet and radio address, Mr. Obama said: "We saw soldiers and civilians alike rushing to aid fallen comrades; tearing off bullet-riddled clothes to treat the injured; using blouses as tourniquets; taking down the shooter even as they bore wounds themselves," he said.
The president said those who responded to the rampage represent the best of America.
Hoping to calm potential ethnic tension, he said the public should remain aware of the diversity of those who defend the U.S.
He said: "They are Christians and Muslims, Jews and Hindus and nonbelievers. They are descendants of immigrants and immigrants themselves. They reflect the diversity that makes this America. But what they share is patriotism like no other."
Authorities have alleged Army Major Nidal Malik Hasan fired at soldiers and civilians on the base before he was shot and wounded by a civilian police officer.
Hasan is a 39-year-old psychiatrist who specialised in trauma counselling at a medical centre on the base.
Authorities believe Hasan fired more than 100 rounds in a soldier processing centre at Fort Hood in the worst mass shooting on a military facility in the United States.
According to his fellow officers, Hasan was conflicted about the fighting in Iraq and Afghanistan. It is believed he was about to be sent to Afghanistan against his wishes.
His doubts had been known for some time because of anti-American propaganda he had been spreading amongst his peers.
Officers have said they did not complain about him for fear of appearing discriminatory against a Muslim.
His family has described him as being a man incapable of the attack, calling him a devoted doctor and devout Muslim who showed no signs of violence.
But they also said he had confided in them that he felt harassed as a Muslim in the US military, and wanted to be treated better.
Officers at the army medical centre at Fort Hood have said Hasan was a quiet man with a strong work ethic who provided excellent care for his patients.
Military officials have not yet said whether Hasan will be charged in a military or civilian court.
Both military and civilian investigators are yet to talk with Hasan, who reportedly jumped up on a desk and shouted "Allahu akbar!" the Arabic for "God is great!” at the start of Thursday's attack.
He was seriously wounded by police and transferred Friday to Brooke Army Medical Centre in San Antonio, where officials gave no indication of his condition except to say he was not able to speak.
