Published: Oct 07, 2010 9:44 PM EDT
Updated: Oct 07, 2010 6:44 PM EDT

JACKSONVILLE, Fla. (AP) - A teen has been sentenced to life in prison for fatally stabbing a Jacksonville man during a robbery.

A Duval County judge sentenced 17-year-old Thomas Diquan Partlow on Thursday. He was convicted in August of first-degree murder. Besides the life sentence, the judge tacked on an additional 45 years for a robbery conviction.

Prosecutors say Partlow stabbed 49-year-old Grady Lane Williamson in January. Partlow and two other boys were driving around when they reportedly decided to rob Williamson for gas money. When the boys searched his pockets after the stabbing, all they found was $3.

A judge previously sentenced Gibson Wright III to 30 years in prison and Marvin Tony Clark to 25 years. They had both pleaded guilty to second-degree murder.