HUNTSVILLE, Texas – A man convicted in the shooting death of a convenience store clerk became the 400th person on Wednesday to be executed in Texas since the state resumed capital punishment in 1982.

Johnny Ray Conner, 32, asked for forgiveness repeatedly and expressed love to his family and his victim’s family, who watched him through windows in the death chamber.

“This is destiny. This is life. This is something Allah wants me to do,” he said. “I’m not mad at you. When I get to the gates of heaven I’m going to be waiting for you. Please forgive me.”

“What is happening to me is unjust and the system is broken,” said Conner, who spoke until the drugs took effect. He was pronounced dead at 6:20 p.m., eight minutes after the lethal drugs began to flow.

Conner was convicted in 1999 for fatally shooting Houston convenience store clerk Kathyanna Nguyen, 49, during an attempted robbery.

Julian Gutierrez, a customer walking inside the store to pay for gasoline, interrupted the holdup, tried to run back outside and was shot in the shoulder. Nguyen was shot in the head.

Conner’s lawyers earlier Wednesday lost an appeal to the U.S. Supreme Court to stop the lethal injection. In arguments rejected by the justices, Conner contended his trial attorneys were deficient for not investigating an old leg injury that left Conner with a limp. The disability would have prevented him from running away from the store quickly.

Gutierrez survived and was among at least three people to identify Conner, whose fingerprint also was found on a bottle at the shooting scene.

Conner was the 21st put to death this year in Texas. Three more are scheduled to die next week.

The prospect of Conner becoming Texas’ 400th executed prisoner prompted an outcry from death penalty opponents.

The European Union, which opposes capital punishment and bans it in its 27 nations, urged Gov. Rick Perry to stop Conner’s execution and impose a death penalty moratorium.

Perry spokesman Robert Black brushed aside the criticism.