By Dan Eggen, Washington Post Staff Writer, Wednesday, March 15, 2006; A05

An FBI agent in Pittsburgh photographed members of an antiwar activist group in 2002, according to documents released yesterday by the American Civil Liberties Union, which said the disclosure marks the latest incident in which the FBI has monitored left-leaning groups.

An FBI report from November 2002 indicates that an agent photographed members of the Thomas Merton Center as they handed out leaflets opposing the impending war in Iraq. The report called the group a "left-wing organization advocating, among many political causes, pacifism."

The same memo notes that one of the leaflet distributors "appeared to be of Middle Eastern descent" but that no other participants appeared to be from the Middle East.

"All we were doing was handing out leaflets, which is a perfectly legal way to spend an afternoon," said Tim Vining, the center's former executive director, who said he participated in the Nov. 24, 2002, protest monitored by the FBI. "All we want to do is exercise our First Amendment rights . . . Is handing out fliers now considered a terrorist activity?"

The FBI said in a statement that the agent was "acting with all appropriate investigative authorities" as part of an ongoing terrorism probe. The photos were destroyed once the agent determined that a person under investigation was not in attendance at the event, the FBI said.

The incident is the latest disclosure by the ACLU involving antiwar protesters, environmental groups and religious organizations that have been monitored by FBI agents or other anti-terrorism investigators.

Another memo from February 2003 said the center was "opposed to the United States' war with Iraq" and described its Web site and activities. That letter was a draft that was never included in an investigative file, the FBI said.

Heavily censored documents from 2005 also refer to information about the center from an unidentified source. An FBI official said those reports were from a separate probe that did not involve terrorism.