Contributed Photo Gutierrez, 53, died while raping a 77-year-old woman, authorities said.

Contributed Photo Gutierrez, 53, died while raping a 77-year-old woman, authorities said.

CORPUS CHRISTI — A man died while raping a 77-year-old woman in Refugio County, a sheriff's investigator said.

Isabel Chavelo Gutierrez, 53, complained to the woman that he wasn't feeling well and stopped having sex with her so he could rest. He then went back to fondling the woman before he rolled over and died, said Sgt. Gary Wright of the Refugio County Sheriff's Office.

Investigators believe Gutierrez died of a heart attack after riding two miles on his bicycle to the woman's home in Tivoli, Wright said. The Nueces County medical examiner is conducting an autopsy.

The woman survived the attack.

Gutierrez was armed with a pocketknife, Wright said. He rode from his own home in Tivoli, where he was registered as a sex offender, according to the state's sex offender registry. He was 5 feet 7 inches tall and weighed 230 to 250 pounds, Wright said. He entered the home by lowering the glass pane on a screen door.

Gutierrez was on parole for sex crimes including aggravated sexual assault and indecency with a child in 1986, Wright said. He was released from prison in 2008.

The woman saw Gutierrez at a local post office one day before the June 2 attack, Wright said.

During the attack, she thought Gutierrez passed out from drinking because she smelled alcohol on his breath.

After he lost consciousness, the woman drove away from her house and called her daughter, who then alerted authorities. Gutierrez was dead when they arrived.