WASHINGTON — Republican Sen. John McCain served on the advisory board to the U.S. chapter of an international group linked to ultra-right-wing death squads in Central America in the 1980s.

The U.S. Council for World Freedom also aided rebels trying to overthrow the leftist government of Nicaragua. That landed the group in the middle of the Iran-Contra affair and in legal trouble with the Internal Revenue Service, which revoked the charitable organization's tax exemption.

The council created by retired Army Maj. Gen. John Singlaub was the U.S. chapter of the World Anti-Communist League, an international organization linked to former Nazi collaborators and ultra-right-wing death squads in Central America. After setting up the U.S. council, Singlaub served as the international league's chairman.

McCain's tie to Singlaub's council is undergoing renewed scrutiny after his campaign criticized Obama for his link to William Ayers, a former radical who engaged in violent acts 40 years ago. Over the weekend, Democratic operative Paul Begala said on ABC's "This Week" that this "guilt by association" tactic could backfire on the McCain campaign by renewing discussion of McCain's service on the board of the U.S. Council for World Freedom, "an ultraconservative right-wing group."

In two interviews with The Associated Press in August and September, Singlaub said McCain became associated with the organization in the early 1980s as McCain launched his political career. McCain was elected to the House in 1982. Singlaub said McCain was a supporter but not an active member. "McCain was a new guy on the block learning the ropes," Singlaub said. "I think I met him in the Washington area when he was just a new congressman. We had McCain on the board to make him feel like he wasn't left out. It looks good to have names on a letterhead who are well-known and appreciated.

"I don't recall talking to McCain at all on the work of the group," Singlaub said.

McCain has said he resigned from the council in 1984 and asked in 1986 to have his name removed from the group's letterhead.

"I didn't know whether (the group's activity) was legal or illegal, but I didn't think I wanted to be associated with them," McCain said in a 1986 newspaper interview.

Singlaub does not recall any McCain resignation in 1984 or May 1986. Nor does Joyce Downey, who oversaw the group's day-to-day activities.

"That's a surprise to me," Singlaub said. "This is the first time I've ever heard that. There may have been someone in his office communicating with our office."