A Southwest D.C. man was sentenced to 50 years in prison Friday for the 2009 shooting death of a teenager who tried to stop a street robbery.

Judge Russell F. Canan sentenced Deangelo Foote, 21, in connection with the July 2009 fatal shooting of Kevin Allen, 17, after a jury in February found Foote guilty of first-degree premeditated murder and other charges.

According to prosecutors, Foote, armed with a handgun, was attempting to rob one of Allen’s friends in an alley off the unit block of N St. SW.

Allen tried to help his friend and struggled with Foote over the gun. The friend ran off, leaving Foote and Allen in the alley. Prosecutors say Foote then shot Allen seven times.

Three witnesses identified Foote as the shooter, including one who called 911 and gave the emergency operator Foote’s name and a detailed description of him.

Foote, who was on probation after an aggregated assault conviction, was also wearing a GPS device on his ankle at the time of the murder.