President Obama on Saturday urged Congress to hold off on any investigation of the Fort Hood rampage until federal law enforcement and military authorities have completed their probes into the shootings at the Texas Army post, which left 13 people dead.

On an eight-day Asia trip, Obama turned his attention home and pleaded for lawmakers to "resist the temptation to turn this tragic event into the political theater." He said those who died on the nation's largest Army post deserve justice, not political stagecraft.

"The stakes are far too high," Obama said in a video and Internet address released by the White House while the president he was flying from Tokyo to Singapore, where Pacific Rim countries were meeting.

Army psychiatrist Maj. Nidal Malik Hasan, 39, was charged on Thursday with the shooting spree at Fort Hood last week. Army investigators have said Hasan is the only suspect and could face additional charges.

Obama already had ordered a review of all intelligence related to Hasan and whether the information was properly shared and acted upon within government agencies. Several members of Congress, particularly Michigan Rep. Peter Hoekstra, the top Republican on the House Intelligence Committee, have also called for a full examination of what agencies knew about Hasan's contacts with a radical Muslim cleric in Yemen and others of concern to the U.S.

Hoekstra confirmed this week that government officials knew of about 10 to 20 e-mails between Hasan and the radical imam, beginning in December 2008.

A joint terrorism task force overseen by the FBI learned late last year of Hasan's repeated contact with the cleric, who encouraged Muslims to kill U.S. troops in Iraq. The FBI said the task force did not refer early information about Hasan to superiors because it concluded he wasn't linked to terrorism.

Lawmakers, however, already have announced they want their own investigations and were frustrated with what they view as a less-than-forthcoming administration.

Rep. Howard McKeon, R-Calif., said he wanted to go ahead with an investigation from the House Armed Services Committee, where he is the top Republican. He said he wanted an investigation that wouldn't compromise law enforcement or military investigations that were continuing on separate tracks.

In the Senate, Sen. Joe Lieberman, a Connecticut independent, said his Homeland Security Committee was opening an investigation.

Obama said he was not opposed to hearings -- eventually. But he strongly pressed lawmakers to hold off until the probes now under way are completed.

"There is an ongoing investigation into this terrible tragedy," Obama said. "That investigation will look at the motives of the alleged gunman, including his views and contacts."

"We must compile every piece of information that was known about the gunman, and we must learn what was done with that information. Once we have those facts, we must act upon them."