Louis Gaskin was convicted in 1990 of two counts of first-degree murder in the killings of Robert and Georgette Sturmfels on Dec. 20, 1989, in Palm Coast. Gaskin shot them from outside the house and then broke in and shot them again. Gaskin then stole items, some of which he gave to his girlfriend as Christmas presents. He was sentenced to death for their murders.

The U.S. Supreme Court Tuesday denied the 56-year-old's request for a stay.

Louis Gaskin's last words

The tan curtain was raised at 6 p.m. Gaskin was strapped down with leather straps on each wrist and a white sheet covered him. IV tubes were taped along each arm.

The white sheet trembled above his feet as officials administered the sedative. There appeared to be a fold in the sheet above the left side of his chest that moved up and down.

Kayla McLaughlin Smith, director of communications for the Department of Corrections, said the execution took place "without incident."

Full coverage: 'Ninja killer' Louis Gaskin executed at Florida prison

Before his execution, Gaskin said "Justice is not about the crime. "It's not about the criminal. It's about the law." He referred to his case and said "Look at my case." Though parts of his statement were difficult to understand.

Body movement ceased after 6:07 p.m., once the sedative took effect. At one point, the man who led the execution pushed on Gaskin's shoulders and yelled, "Wake up!" to check if he was asleep. There was no reaction.

After 11 minutes, the official asked someone to come in. A woman in a white lab coat walked in and checked Gaskin's eyes. She then placed a stethoscope on several places on his chest and neck area. She then said something to the official who then said, "The sentence of the state of Florida was carried out at 6:15 p.m."

The protestors had left the area by the time reporters returned to the staging area.

Among the approximately 23 witnesses were 7th Circuit Judge Raul Zambrano and 7th Circuit State Attorney R.J. Larizza.

Louis Gaskin put to death for 1989 murders

Convicted murderer Louis Gaskin, also known as the "ninja killer," was put to death via lethal injection at 6:15 p.m. at Florida State Prison in Raiford.

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Previous coverage: With his execution looming, Louis Gaskin describes attack on second Palm Coast couple

Death penalty opponents begin to arrive

Two protestors are sitting outside of the designated protest area. They declined to comment. More are expected to arrive by 5 p.m.

There's also an area for death penalty supporters.

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Gaskin's last morning

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Gaskin woke up at 4:45 this morning. At 9:45 a.m., he had his last meal, which consisted of barbecue pork ribs, Buffalo wings, pork and turkey neck, shrimp fried rice, French fries and water.

Gaskin was offered a sedative, as is customary for executions, but Smith, director of communications for the Department of Corrections, would not comment on whether he accepted it.

Gaskin's sister visited him earlier today, according to Smith. His relatives are not allowed to attend the execution. Gaskin did not have a spiritual advisor visit him, Smith said.

Victims or relatives of victims are not attending the execution, Smith said.

She described Gaskin as calm and in good spirits.

Photos from the 1989 crime scene

Victim speaks out: Noreen Rector, one of Gaskin's victims, opposes execution, has strong words for DeSantis

This article originally appeared on The Daytona Beach News-Journal: 'Ninja killer' Louis Gaskin received lethal injection