Two weeks after a man was accused of terrorizing the New York City subway system, prosecutors and his defense attorneys are sparring over an FBI jailhouse visit to the suspect.

Defense attorneys claimed in a court filing Thursday that agents unexpectedly and improperly took DNA samples from Frank James, who allegedly wounded 10 people when he opened fire inside a crowded Brooklyn subway car.

Papers filed in Brooklyn federal court claimed FBI agents entered James' cell, questioned him and took multiple swabs of his inner cheeks for DNA. The defense lawyers also suggested the agents didn't have a search warrant.

"Contrary to standard practice, the government committed this intrusion absent advance notice to counsel, depriving us of an opportunity to be heard or to be present," the lawyers wrote. They said the search took place Tuesday.

Later Thursday, prosecutors responded by calling the claims "hyperbole." They said no questioning took place and that the "DNA was obtained pursuant to a judicially authorized search warrant" that could have been known about in advance.

Authorities say James unleashed smoke bombs and dozens of bullets on April 12 in a train full of morning commuters. Several people were injured, but no one was killed.

James, 62, is charged with a federal terrorism offense that applies to attacks on mass transit systems. Authorities say there's currently no evidence linking James to terror organizations, leaving his motives murky.