The Boston Police Department reports the arrest of Lavonrence Perkins, 20, for the shooting death of Cordell McAfee on May 10.
Police say Perkins had been hiding out in Providence, and was arrested with the help of Rhode Island State Police and the US Marshal's office.
McAfee was found with multiple gunshot wounds at Dorchester Avenue and Roseland Street on the evening of May 7.
McAfee was the state's star witness in the first case against gang members for the shocking death of 10-year-old Trina Persad in 2002. At trial, McAfee, himself only 15 at the time of her death, testified he and other members of his gang went in search of some rival gang members to avenge a shooting attempt. McAfee testified that when they found them on a Roxbury basketball court, a member of his gang opened fire with a shotgun - hitting Trina instead.