Ayers asks what he could add to discussion

CHICAGO, Oct. 15 (UPI) -- The Chicago '60s radical whose association with Barack Obama Republicans say leads to questions about the Democrat's judgment is keeping a low profile.

William Ayers co-founded the anti-war Weather Underground but now is a University of Illinois at Chicago professor on a previously scheduled sabbatical. Republican presidential hopeful John McCain and his surrogates question the depth and breadth of his relationship with Obama, who says the two served on a board together, the Chicago Tribune reported Wednesday.

"What could I possibly add? Life happens," the anti-war activist told the Tribune.

Ayers participated in the bombings of New York City Police Headquarters in 1970, the U.S. Capitol in 1971 and the Pentagon in 1972. He went underground during the 1970s following an explosion in which two fellow Weathermen were killed.

McCain and others say Obama must explain the extent of his relationship with Ayers and told a St. Louis radio station Tuesday he likely would bring up Ayers during the candidates' Wednesday night debate. Obama, who has condemned Ayers' violent actions of the part, has a counter radio ad ready.

The criticism of Ayers is shocking to some of his colleagues, the Tribune reported.

Ayers is seen as "a really nice guy," said Phillip Kisunzu, a post-doctoral research assistant in the Curriculum and Instruction Department. Kisunzu said he recently asked Ayers about the furor.

"I brought it up because I hear his name on the news," Kisunzu told the Tribune. "I heard it again today (Tuesday)."