TALLAHASSEE, Fla. (AP) — A Florida man who fatally stabbed his estranged wife's sister and parents and then set fire to their house is scheduled for execution in Florida under a death warrant signed by Republican Gov. Ron DeSantis.

David Pittman, 63, is set to die Sept. 17 in the record-extending 12th execution scheduled for this year. DeSantis signed the warrant Friday, as two other men, Kayle Bates and Curtis Windom, await execution later this month.

The highest previous annual total of recent Florida executions is eight in 2014, since the death penalty was restored in 1976 by the U.S. Supreme Court. Florida has already executed nine people this year, more than any other state, while Texas and South Carolina are tied for second place with four each.

A total of 28 people have been executed so far this year in the U.S., exceeding the 25 executions carried out last year. It ties 2015, when 28 people were also put to death.

Pittman was convicted and sentenced to death in 1991 on three counts of first-degree murder, according to court records. Jurors also found him guilty of arson and grand theft.

Pittman and his wife, Marie, were going through a divorce in May 1990, when Pittman went to the Polk County home of her parents, Clarence and Barbara Knowles, officials said. Pittman fatally stabbed the couple, as well as their younger daughter, Bonnie. He then set fire to the house and stole Bonnie Knowles' car, which he also set on fire, investigators said.

A witnessed identified Pittman as the person running away from the burning car. A jailhouse informant also testified that Pittman had admitted to the killings.

The Florida Supreme Court is already scheduled to hear an appeal. An appeal will also likely be filed with the U.S. Supreme Court.