Richard Cobb, who was convicted for a 2003 slaying and abduction of a Cherokee County man, is set to die Thursday evening in Huntsville.

The 29-year-old testified at his trial he was forced to fatally shoot 37-year-old Kenneth Vandever because of threats from his accomplice, Beunka Adams who was executed last year.

Vandever was abducted during a convenience store robbery and later shot to death. Two women also abducted from the store were shot and left for dead. One of them was raped. But they survived and testified against their attackers.

Attorneys for Cobb are asking the U.S. Supreme Court to stop the punishment. It would be the fourth execution this year in Texas.