STARKE, Fla. -- A Florida inmate convicted of raping and killing a college student decades ago screamed and yelled "murderers!" three times, thrashing on a gurney as he was being put to death Thursday. The governor's office said Eric Scott Branch, 47, was pronounced dead at 7:05 p.m. Thursday after receiving a lethal injection at Florida State Prison.

Branch was convicted of the 1993 rape and fatal beating of University of West Florida student Susan Morris, 21, whose naked body was found buried in a shallow grave near a nature trail.

Just as officials were administering the lethal drugs that included a powerful sedative, Branch let out a loud, blood-curdling scream, thrashed about on his gurney and then yelled "murderers! murderers! murderers" before falling silent with a guttural groan.

Get Breaking News Delivered to Your Inbox

Moments earlier, he had addressed the corrections officers in the room with him by saying that, instead of them carrying out the death sentence, it should have been Gov. Rick Scott and Attorney General Pam Bondi, both Republicans.

"Let them come down here and do it. I've learned that you're good people and this is not what you should be doing," Branch told the officers.

Asked whether Branch's scream could have been caused by the execution drugs, Department of Corrections spokeswoman Michelle Glady said afterward that "there was no indication" that the scream was cause by the lethal injection procedure. She said that conclusion had been confirmed by the Florida Department of Law Enforcement.

After Thursday's execution, the Morris family issued a statement saying they are still mourning the victim's death a quarter century ago.

"Twenty-five years ago, Susan's life was suddenly and brutally extinguished. We have grieved for her longer that she was with us. Yet because of who she was ... she will never be forgotten by those who love her," said the statement read out by the victim's sister, Wendy Morris Hill.

Outside the prison, Herman Lindsey joined anti-death penalty protesters. Lindsey, a former death row inmate who was exonerated in 2009, said he wants to see the practice abolished.

"There's no way to guarantee we're not killing innocent people," he said.

Evidence in the case shows that Branch approached Morris after she left a night class on Jan. 11, 1993, so he could steal her red Toyota and return to his home state of Indiana. He was arrested while traveling there.

In denying one of Branch's appeals, the Florida Supreme Court noted that the crime was particularly brutal.

"She had been beaten, stomped, sexually assaulted and strangled. She bore numerous bruises and lacerations, both eyes were swollen shut," the justices wrote.

Branch also was convicted of sexually assaulting a 14-year-old girl in Indiana and of another sexual assault in Panama City, Florida, that took place just 10 days before the fatal attack on Morris, court records show.

The jury in his murder case recommended the death penalty by a 10-2 vote under Florida's old capital punishment system, which was ruled unconstitutional by the U.S. Supreme Court in 2016. The high court said juries must reach a unanimous recommendation for death and judges cannot overrule that. Florida legislators subsequently changed the system to comply.

One of Branch's final appeals to the U.S. Supreme Court involved whether he deserved a new sentencing hearing because of that jury's 10-2 vote in his 1994 trial. The Florida Supreme Court has ruled that the new system of sentencing does not apply to inmates sentenced to death before 2002.

Branch claimed in a last-minute appeal that the Florida court's decisions on which inmates get new sentencing hearings and which do not is unfair and arbitrary. In court documents, Branch's lawyers say this prohibits about 150 Florida death-row inmates from having their sentences reviewed.

The U.S. Supreme Court, without comment, rejected that appeal Thursday and one other Branch's attorneys had filed.

The Florida Supreme Court had denied a stay of execution in the Branch case on Feb. 6, leaving him with only limited appeals in federal courts.

Corrections Department spokeswoman Michelle Glady said Branch had been visited by his daughter Thursday morning and refused a meeting with a spiritual adviser. For a last meal, he had a pork chop, T-bone steak, French fries and ice cream.

Elsewhere, Texas Gov. Greg Abbott spared the life Thursday of a convicted killer shortly before the man's scheduled execution for masterminding the fatal shootings of his mother and brother.

In sparing the life of Thomas "Bart" Whitaker about an hour before he was scheduled for lethal injection, Abbott accepted the state parole board's rare clemency recommendation. Whitaker's father, Kent, also was shot in the 2003 plot at the family's suburban Houston home but survived and led the effort to save his son from execution. Abbott commuted the sentence to life without parole.

In Alabama, Doyle Lee Hamm was sentenced to die Thursday evening for the 1987 death of a motel clerk during a robbery. But Hamm fought his death sentence, arguing there was a risk of a botched execution because of damage to his veins due to lymphoma and other illnesses. The U.S. Supreme Court on Thursday evening temporarily delayed the lethal injection procedure as it considered his request for a permanent stay.