Sources : Crowley 's exit was in the works for months , a MIT official says . Crowley says he takes responsibility for his remarks on Chelsea Manning . He made the comments in a talk last week at MIT . Manning is being held under suspicion that he leaked classified documents .
NEW : Crowley 's exit was in the works for months , White House official says . Crowley says he takes responsibility for his remarks on Bradley Manning . He made the comments in a talk last week at MIT . Manning is being held under suspicion that he leaked classified documents .