WASHINGTON -- The Pentagon is launching an urgent review of whether military procedures hinder the identification of service members who pose a threat to their fellow troops.

Along with that 45-day examination, Defense Secretary Robert Gates yesterday ordered an in-depth investigation, lasting four to six months, into whether Army policies and procedures played any role in failing to prevent the Nov. 5 shooting deaths at Fort Hood in Texas.

Word of the Pentagon reviews came the same day as a Senate committee held the first public hearing into the attack that killed 13 people and wounded 30 others at the Army post.

Homeland Security and Governmental Affairs Chairman Joseph Lieberman, I-Conn., began the hearing by saying he believed that the incident was "a terrorist attack." He added that senators wanted "to determine whether that attack could have been prevented, whether the federal agencies and employees involved missed signals or failed to connect the dots."

As more becomes known about the behavior of the alleged gunman, Maj. Nidal M. Hasan, prior to the shootings, pressure has mounted on the administration and military to explain why the Army psychiatrist didn't warrant further investigation or preemptive action.

U.S. intelligence officials knew last year that Maj. Hasan had been corresponding with a radical Islamic cleric; earlier this year, investigators learned of Internet postings, allegedly by Maj. Hasan, that indicated sympathy with suicide bombers; and colleagues of Maj. Hasan's at Washington's Walter Reed Army Medical Center, where he was stationed before going to Fort Hood, said the "intensity" of his embrace of Islam raised concerns among doctors there.

Mr. Gates said the Army's "in-depth, detailed assessment" would look at "whether the Army programs, policies and procedures reasonably would have prevented the shooting." The goal, he said, is "to determine whether, in fact, there were lapses or problems."

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