WASHINGTON, D.C. -

A diplomat suspected of killing his wife, mother and three sons in 1976 has been added to the FBI's list of "Ten Most Wanted Fugitives."

William Bradford Bishop Jr. allegedly bludgeoned his family to death in their suburban Washington home. Authorities say he then drove 275 miles to North Carolina, where he dumped the bodies in a wooded area and burned them. The victims' bodies weren't identified until a week later, giving Bishop ample time to plot a getaway.

Investigators have said it's possible that Bishop fled to Europe and assumed a new identity. He is fluent in five languages.

People on the FBI's most wanted list have included Osama Bin Laden and James Earl Ray, who assassinated Dr. Martin Luther King Jr.

Bishop was added Thursday.