James ``Whitey'' Bulger and his once-loyal right-hand man have had an angry, profanity-laced exchange in court during Bulger's racketeering trial in Boston.

    Tensions exploded Tuesday after Kevin Weeks called Bulger and his partner, Stephen ``The Rifleman'' Flemmi, ``the biggest rats,'' referring to their work as FBI informants.

    Bulger swore at Weeks, who then loudly swore back at Bulger and said ``What are you going to do?''

    Judge Denise Casper had to step in and restore order. She reminded Bulger that his lawyers are to speak for him in court.

    Weeks says he decided to cooperate and testify after learning that Bulger and Flemmi were longtime FBI informants.

    Weeks is on the stand for a second day in Bulger's trial for allegedly participating in 19 murders in the 1970s and 1980s.  (Associated Press)