President Obama on Tuesday told 15,000 mourners at Fort Hood, Texas, that no religious faith could justify the murderous attack by a Muslim U.S. Army officer on his fellow soldiers last week, the president's first acknowledgment that fanatical Islam may have motivated the shooter.
"No faith justifies these murderous and craven acts. No just and loving God looks upon them with favor," Mr. Obama said. "And for what he has done, we know that the killer will be met with justice, in this world and the next."
Mr. Obama has urged caution before concluding that Army Maj. Nidal Malik Hasan - whom Mr. Obama never mentioned by name - fatally shot 12 soldiers and one civilian, while wounding 29, because of his Muslim faith. Army Chief of Staff Gen. George Casey has expressed concern in the wake of the rampage about a backlash within the military against Muslims in the different service branches.
But the president's comments were a recognition that the growing body of evidence that has come out since last Thursday's shooting reveals a suspect who was deeply opposed to many of the U.S. military's current operations in the Middle East because of his Muslim faith.
U.S. officials told the Associated Press on Monday that a Pentagon worker on a terrorism task force had looked into Maj. Hasan's background months ago and had concluded he did not merit further investigation.
Two officials said the group had been notified of communications between the major and a radical imam overseas, and the information had been turned over to a Defense Criminal Investigative Service employee assigned to the task force. The two spoke on the condition of anonymity because they were not authorized to discuss the investigation, the wire service reported.
The White House said it is actively investigating why Maj. Hasan was allowed to remain on the base in light of his communication with Anwar al-Aulaqi, a cleric who taught at a mosque in Northern Virginia before Sept. 11, 2001, and had links to the September 11 hijackers.
"The president has asked every agency involved and everybody that ... would have had some purview over this to investigate why this happened, how this happened, and to ensure that they can tell him that it won't happen again," said White House press secretary Robert Gibbs.
Mr. Gibbs steered clear of the questions surrounding Maj. Hasan's faith.
"Obviously, there are people ... of all faiths and all ethnicities serving with distinction and valor in our armed services today. The investigation is ongoing to figure out what would motivate an individual to carry out the type of act that this major carried out," Mr. Gibbs said.
Most of the president's speech at III Corps headquarters was given to eulogizing the 13 men and women killed in the attack, one of them a newly pregnant young mother.
"Here, at Fort Hood, we pay tribute to 13 men and women who were not able to escape the horror of war, even in the comfort of home," Mr. Obama said.
"Neither this country - nor the values upon which we were founded - could exist without men and women like these 13 Americans. And that is why we must pay tribute to their stories."
Mr. Obama named each of the victims and spoke about the lives they touched and the loved ones they will leave behind. He also paid tribute to the current generation of soldiers, saying that in "a world of threats that knows no borders," they have shown themselves the equals of earlier generations of American soldiers.
The president spoke on a stage that displayed, around the front, the combat boots of those killed. A large portrait of each victim was on display. Into each pair of boots was inserted a machine gun, on top of which was propped a combat helmet.
After his remarks and the playing of taps, Mr. Obama and first lady Michelle Obama stopped in front of each of the memorials before departing the ceremony. The president placed a commander-in-chief's coin next to each photo of the fallen.
After the president left, family, friends and colleagues filed slowly past the memorials, many openly weeping.
The president and Mrs. Obama spent time before the speech with families of those killed and with people who were injured during the attack. After his speech, he went to the base hospital to visit wounded people still there.
The ceremony unfolded in a field at the headquarters of the massive post, cordoned off with walls of steel shipping containers. Many soldiers in the crowd listened intently to Mr. Obama's speech, standing stoically, some with heads bowed.
Sheila Wormuth, whose husband is stationed at Fort Hood, came with her 3-year-old daughter to show their support. While her husband was not at the shooting site, she said, "what happens to my husband's brothers and sisters happens to us."
"It means everything to the people that work here. Its the president of the United States," said Lt. Col. Tommy E. Eberhart.
• This article was based in part on wire service reports.