BOSTON (AP) -- As prosecutors wind down their case against James "Whitey" Bulger this week, one of their most important witnesses is providing grisly testimony about a string of killings.
Bulger's former partner, Stephen "The Rifleman" Flemmi, is expected to continue his testimony Monday.
On Friday, Flemmi described a series of killings Bulger is accused of participating in during the 1970s and '80s.
The 83-year-old Bulger is accused of playing a role in 19 killings. Flemmi pleaded guilty in 10 murders and is now serving a life sentence.
Bulger has pleaded not guilty. His lawyers have vehemently denied the prosecution's claim that Bulger was a longtime FBI informant.
Bulger has also strongly denied killing two women, including Flemmi's girlfriend.
Prosecutors say they expect to rest their case this week, following by defense testimony.