FARGO (AP) - A teenager who was sentenced to life in prison for killing his sister has now been charged as an adult in an escape attempt from a Fargo juvenile detention center.

Sergei Carlson is charged in the incident last month in which a detention center guard was struck with a piece of wood from a bookcase. The guard suffered minor injuries but the escape attempt failed.

A statement from the Cass County State's Attorney's office Tuesday said the 16-year-old Carlson has been charged with escape and assault of a corrections officer, both felonies. His first appearance on the charges is scheduled this morning.

The teenager was sentenced last week to life in prison, with the possibility of parole, on charges of murder and a deviate sexual act in the July 2007 death of his 16-year-old sister, Whitney.

Carlson was moved from the detention center to the county jail after the attack on the guard.