TALLAHASSEE, Fla. (AP) — One of the longest-held inmates on Florida's death row is set to be executed Thursday for two separate killings in 1984, the fatal stabbing of a 14-year-old babysitter as two children in her care were sleeping and the other a hammer attack on a mother of two.

Duane Owen is scheduled to receive a lethal injection at 6 p.m. EDT at Florida State Prison in Starke. He drew death sentences for the March 24, 1984, rape and stabbing attack on Karen Slattery, 14, and for the rape and killling of Georgianna Worden, 38, in May 1984, both in Palm Beach County.

Owen attacked two other women in Palm Beach County who survived. All four attacks occurred just before and after Owen’s 23rd birthday. Now 62, Owen is one of 293 people on Florida’s death row and one of the longest residing there. Besides his death sentences, he also received six life sentences.

If the lethal injection is carried out, it would be Florida’s fourth execution this year after none since 2019. Republican Gov. Ron DeSantis signed each of the death warrants in the months before announcing he is running for president.

Slattery was repeatedly stabbed and raped in a home in Delray Beach while two children in her care were sleeping.

Two months later, Worden was sleeping in her Boca Raton home when Owen struck her several times with a hammer and raped her. One of Worden's children found her body the next morning while getting ready for school, according to court records.

Delray Beach and Boca Raton are both about 50 miles (80 kilometers) north of Miami, in Palm Beach County.

Owen's lawyers argued that he shouldn't be executed on grounds of insanity. The state Supreme Court rejected his latest appeal last week and the U.S. Supreme Court rejected it Wednesday.

A defense psychologist testified earlier this month that Owen believes he absorbed the souls of his victims and that they still exist inside him. Owen's lawyers had argued that he is schizophrenic and suffers from delusions.

Prosecutors argued that while Owen has mental health issues, nothing would preclude him from being executed because he's aware it's a punishment for his crimes. Psychiatrists for the state testified that Owen's schizophrenia is an act that he discusses when being evaluated, but he otherwise shows no signs of the illness.

And while the defense argued Owen has dementia and gender dysphoria, psychiatrists for the state said Owen has a good memory, doesn't appear to present himself as female and that gender dysphoria doesn't make people more aggressive or cause delusional thinking. They said instead, Owen is sexually sadistic, according to court records.

Owen's mother died when he was 11 and his father took his own life when he was 13, court records indicate. They add that he was the victim of physical and sexual abuse as a child.