CLEVELAND -- Convicted murderer Billy Slagle, who was scheduled to be executed Aug. 7 for killing a Cleveland woman in 1987, was found hanged in his cell Sunday morning, authorities said.

Slagle was found in his Chillicothe Correctional Institution cell just hours before he was set to be put on suicide watch, said JoEllen Smith, spokeswoman for the Ohio Department of Rehabilitation and Correction.

Slagle, 44, murdered his 40-year-old neighbor Mari Anne Pope in her Clinton Avenue home during a burglary. He stabbed Pope 17 times with a pair of scissors as two children she was babysitting watched.

Pope prayed during the attack, the children said.

"I feel Billy Slagle is now responsible for the lives of three people: [Mari Anne], my son and his own," said Lauretta Keeton, the mother of the witnesses.

Keeton's son committed suicide in 2002 and was "troubled his whole life by what he saw Slagle do," she said.

Slagle was found just after 5 a.m. and was pronounced dead about an hour later, Smith said, adding that the department is conducting a review of the apparent suicide and no further details are available.

The department's policy is to place death row inmates on suicide watch beginning 72 hours before their scheduled execution, Smith said.

Last month, Gov. John Kasich denied Slagle clemency after the Ohio Parole Board again recommended Slagle's execution.

The parole board made the same recommendation in 2011, but Kasich gave Slagle reprieve and delayed the execution while a federal judge reviewed Ohio's execution procedures.

Kasich had no comment about Slagle's death, his spokesman said.

Cuyahoga County Prosecutor Timothy J. McGinty called on the parole board to commute Slagle's sentence to life in prison.

McGinty was not willing to speak about the hanging, his spokesman said.

Slagle's defense team had no warning that he might commit suicide, one of his public defenders, attorney Vicki Werneke, told the Associated Press in an e-mail.

Slagle's lawyers asked for mercy, citing Slagle's age at the time of the murder and his addiction to drugs and alcohol.

Slagle was 18 when he murdered Pope. He broke into her home looking for money to buy alcohol.

The young man had been a product of a dysfunctional family, lawyers said.

Slagle told authorities that his judgement was impaired by alcohol and marijuana when he committed the murder and that the crime did not reflect who he was as a person, according to a clemency report.

A self-described loner, Slagle began using marijuana when he was 12 years old, he said.

Pope's murder was not Slagle's first time exploding into violence.

The year before the fatal stabbing, Slagle attacked a married couple he lived with.

Slagle struck the wife in the head with a meat hook and stabbed her husband in the leg with a pair of scissors after the couple asked Slagle to move out.

Slagle was sentenced to death in 1988.