Anthony Haynes was put put to death by lethal injection Thursday night for the slaying of an off-duty Houston police officer.

Haynes, 33, was convicted for the May 1998 murder of Kent Kincaid.

Sgt. Kincaid, 40, and his wife Nancy were driving near their home in the Copperfield area of west Harris County when their windshield was struck by a foreign object, which they believed was thrown from a passing truck. Kincaid followed the vehicle for several blocks before confronting the driver of the truck, according to an account from the Houston Police Officers' Union. Kincaid informed the driver that he was a police officer and was reaching for his ID when Haynes pulled a gun and shot him in the head. Investigators later identified the foriegn oject that struck the Kincaids' car to be a bullet fired from the same gun that was used to shoot Kincaid.

Haynes, then 19, was arrested within a few days of the shooting. He confessed in taped recordings with investigators that he was the driver of the pickup and that he shot Kincaid, Michael Graczyk wrote for the Associated Press. Haynes was sentenced to death September 1999.

The 5th U.S. Circuit Court of Appeals rejected an appeal Monday to stop Haynes' execution. Haynes' attorneys claim he had poor legal help during his trial and shouldn't be put to death, the AP reported.

The Texas Board of Pardons and Paroles rejected Haynes' requests Tuesday to recommend his death sentence be commuted to life in prison, or alternately, to recommend to Gov. Rick Perry that his execution be stayed for 90 days to allow a review of his case,  Allan Turner reported in the Houston Chronicle .

Haynes was the second of four inmates scheduled for execution in Texas during October, the most of any month in 2012, according to the Texas Department of Criminal Justice.