US Army Chaplain Col. Frank Jackson (pictured), has told mourners to pray for the Fort Hood shooter and his family. Photo / AP/LM Otero

US Army Chaplain Col. Frank Jackson (pictured), has told mourners to pray for the Fort Hood shooter and his family. Photo / AP/LM Otero

FORT HOOD, Texas - Mourners were asked to pray for the man authorities say went on a shooting spree at the Fort Hood military base and his family.

An Army chaplain exhorted his congregation on Sunday to draw together even if the gunman's motives may never be fully known.

"Lord, all those around us search for motive, search for meaning, search for something, someone to blame. That is so frustrating," Colonel Frank Jackson told a group of about 120 people gathered at the post's chapel.

Jackson asked worshippers to pray for the 13 dead and 29 wounded that Major Nidal Malik Hasan, an Army psychiatrist, is accused of shooting, but also asked them to pray for Hasan and his family "as they find themselves in a position that no person ever desires to be."

"And Lord, teach us to love and pray for those who rise up against us and pray for those who do us harm. We pray for Major Hasan," Jackson said.

At least 16 victims remained hospitalized with gunshot wounds Sunday, and seven were in intensive care.

Military criminal investigators continue to refer to Hasan as the only suspect in the shootings Thursday but won't say when charges would be filed.

Hasan, who was shot by civilian police to end the rampage, was in critical but stable condition at an Army hospital in San Antonio.

He was breathing on his own after being taken off a ventilator on Saturday, but officials won't say whether Hasan can communicate.

A government official speaking on condition of anonymity because the person was not authorized to discuss the case said an initial review of Hasan's computer use has found no evidence of links to terror groups or anyone who might have helped plan or push him toward the attack.

The review of Hasan's computer is continuing, the official said.

Army investigators on Sunday were searching for additional evidence to put together a comprehensive bullet trajectory analysis.

Investigators were "seeking any military or civilian personnel who may have left the scene ... with gunshot damage such as damaged privately owned vehicles," Fort Hood spokesman Chris Haug said in a statement.

Hasan likely would face military justice rather than federal criminal charges if investigators determine the violence was the work of just one person.

Sen. Joe Lieberman, chairman of the Senate Homeland Security and Governmental Affairs Committee, said he plans to begin a congressional investigation to determine whether the shootings constitute a terrorist attack.