(Agencies)
Updated: 2008-03-07 10:26

WASHINGTON -- Capitol Hill offices received letters Thursday containing a photo of the Times Square military recruiting office before it was bombed and including the claim "We Did It." The manila envelopes contained a photo of a man standing in front of the recruiting station before it was bombed.

The photo was the kind commonly sent as a holiday greeting card, according to a Democratic aide who spoke on condition of anonymity because the matter is under investigation.

This photo released by the New York Police Dept. from a private security camera shows an explosion at the Times Square military recruiting station Thursday morning March 6, 2008 in New York. [Agencies]

The message on the card: "Happy New Year, We Did It."

The envelope also contained a packet of approximately 10 sheets of paper that seemed to be a political manifesto railing against the Iraq war and a booklet. The aide didn't know what the booklet was. A second aide, who also spoke on condition of anonymity, said similar letters arrived in as many as 10 offices.

Capitol Police, FBI and US Postal Inspection Service officials said they were investigating.

Related readings:  Small bomb explodes in Times Square

The man in the photo was thin, white with graying hair, wearing a striped flannel shirt and jeans, the Democratic aide said. A law enforcement official, who spoke on condition of anonymity because the case is ongoing, confirmed some of the contents of the letters as described by the aide.

The Associated Press obtained a copy of an e-mail sent from the office of Sen. Dianne Feinstein, D-Calif., to other lawmakers Thursday that reads:

"A few offices on the House side have received a letter today addressed to 'Members of Congress' with a picture of a man standing in front of the Times Square recruiting station that was bombed in New York today with the statement 'We did it.' He is standing in front of it with his arms spread out and he's attached his political manifesto."

Authorities advised the recipients to leave the letters alone and call police, the e-mail says. Feinstein spokesman Scott Gerber referred calls to Capitol Police.

The small bomb caused minor damage to the New York military recruiting station before dawn Thursday and police were searching for a hooded bicyclist seen on a surveillance video pedaling away.

The blast left a gaping hole in the front window and shattered a glass door, twisting and blackening its metal frame. No one was hurt, but Police Commissioner Raymond Kelly said the device, though unsophisticated, could have caused "injury and even death."