LUCASVILLE — An Ohio man said he was “heartily sorry” before he was executed this morning for the murders of five children in a 1992 Cincinnati apartment fire he set in an attempt to destroy evidence of a burglary.

William Garner, 37, died by lethal injection at 10:38 a.m. at the Southern Ohio Correctional Facility.

As he lay on the execution table, Garner held a dreadlock of hair from a female friend and read a lengthy final statement from notebook paper held by the execution team leader, thanking several people as well as the state of Ohio.

“God bless everyone who has been robbed in this procedure,” he said. “I thought I’d never be free, but I’m free now.”

In the pre-dawn hours of Jan. 26, 1992, Garner gained access to Addie Mack’s apartment after stealing keys from her purse while she received care in a hospital emergency room. Six children, ages 8 to 13, were at the apartment alone, and Garner knew they were there when he threw a lit match onto a couch.

Garner has admitted setting the fire but said he thought the children would escape. Only one, 13-year-old Rod Mack, made it out alive. Mack watched the execution quietly with several others.

So many people wanted to witness the execution on behalf of the young victims that the prison opened a second viewing room, prisons spokeswoman Julie Walburn said. Mack and five others were accommodated in the witness room facing the execution chamber, and another three watched on closed-circuit TV in the spillover room, she said.

Garner spent his final hours watching television and talking on the telephone with a friend and his twin brother. He visited with his mother and other relatives, as well as with spiritual advisers and his legal team, and took Holy Communion about an hour and a half before the start of his execution.

Garner had said a secondary motivation for setting the fire was to draw attention to the children’s squalid living conditions. He told police that he had noticed the bedroom “full of girls” and that one of them had asked him for water, which he provided, according to a report by the Ohio Parole Board. He also said he had been in another bedroom where the two boys slept.

His lawyers had argued that the death sentences be set aside because Garner had developmental disabilities, a limited IQ and a violent, abusive upbringing that caused him to function on the level of a 14-year-old at the time of the deaths.

Garner is the sixth person executed in Ohio this year and the 39th put to death by the state since it resumed the practice in 1999.