Attorney General Eric Holder says he was disturbed to learn of contacts between Fort Hood shooting suspect Nidal Hasan and a radical imam overseas.
Holder is testifying Wednesday before the Senate Judiciary Committee.
Lawmakers asked him about the mass shooting at the Texas Army base, and Holder says the government is conducting a thorough review of Hasan's background to determine if internal warning signs were missed before the shooting.
On the basis of what he knows now, the attorney general says, he found the contacts between Hasan and the imam "disturbing."
Investigators have said e-mails between Hasan and the imam did not advocate or threaten violence. Holder says investigators are still gathering evidence in the case.