BEAVER, Pa. — One of three defendants charged in what prosecutors say was a robbery during a drug deal that claimed two lives has been convicted of third-degree murder.

The Beaver County Times ( ) reports that jurors deliberated for more than 20 hours before convicting 18-year-old Ronald Foster of the charge as well as robbery, conspiracy and criminal use of a phone. He will be sentenced next month.

Jurors acquitted him Tuesday of second-degree murder in the slayings in Aliquippa last fall of 18-year-old Dane Mathesius and 16-year-old William Booher. Booher was found shot to death in a car. Mathesius fled and was found dead nearby several days later.

Defense attorney Paul Gettleman argued that his client had nothing to do with the shootings and “just wanted to buy some weed.”

Information from: Beaver County Times,