A Texas inmate has been executed for fatally shooting one of three people he and a partner abducted during a convenience store robbery nearly 11 years ago.

Twenty-nine-year-old Richard Cobb received lethal injection Thursday evening for using a 20-gauge shotgun to kill Kenneth Vandever in an East Texas field where two women also were shot and one was raped.

The punishment was carried out after the U.S. Supreme Court rejected a last-day appeal.

Cobb's lawyers contended a prison expert gave false testimony at Cobb's trial in 2004 that tainted his punishment. State attorneys argued the testimony was accurate and the appeal was a meritless attempt to delay the execution.

It's the fourth execution this year in Texas. Cobb's partner, Beunka Adams, was put to death a year ago.