Arlen Specter, chairman of the Senate Judiciary Committee.

    BEIJING, Sept. 22 (Xinhuanet) -- The Senate Judiciary Committee chairman accused the Pentagon Wednesday of obstructing an inquiry into claims that the U.S. military identified four Sept. 11 hijackers more than a year before the 2001 attacks.

    The Pentagon barred several witnesses from testifying before the Senate Judiciary committee at a public hearing on Wendesday.

    The witnesses were expected to testify about a link between al-Qaida and four of the Sept. 11 hijackers, including leader Mohamed Atta, that a secret military unit "Able Danger" is said to have uncovered more than a year before the attacks.

    Before Wednesday's hearing, Paul Swiergosz, a Defense Department spokesman, said that public testimony about "Able Danger" would be inappropriate.

    "We have expressed our security concerns and believe it is simply not possible to discuss Able Danger in any great detail in any public forum," Swiergosz said.

    A second spokesman, Bryan Whitman, said the Pentagon believes it has provided sufficient information on Able Danger to the Senate Armed Services and Intelligence Committees, which oversee the Defense Department.

    "I think the Department of Defense owes the American people an explanation of what went on here," said Arlen Specter, chairman of the Senate Judiciary Committee.

    Curt Weldon, one of the witnesses, was the first to come forward to assert that Able Danger had identified Atta and three others as being members of al-Qaida. If correct, the intelligence would change the timeline for when the government first became aware of Atta's links to al-Qaida. Enditem

    (Agencies)