U.S. authorities have captured an alleged gangster linked to 19 murders after he had been on the run for more than 16 years.

The Federal Bureau of Investigation said it arrested James (Whitey) Bulger, along with his longtime girlfriend, Catherine Greig, on Wednesday evening at a house in Santa Monica, California.

The 81-year-old Bulger was the leader of the violent Winter Hill Gang in Boston, Massachusetts. It was a largely Irish mob that ran several criminal ventures. He fled in 1995 after being tipped by a former FBI agent that he was about to be charged.

Bulger, nicknamed Whitey for this shock of bright platinum hair, was once an FBI informant. He provided the law enforcement agency with tips about his gang's main rival, the New England Mob.

His legend as a fugitive seemed to grow over the years, with numerous books written about him. He was an inspiration for a 2006 film, The Departed.

The arrest of Bulger and the 60-year-old Greig came less than two days after the FBI sparked new interest in the case through the use of a 30-second ad during daytime television shows aimed at women about Greig's age.