The heat wave gripping Oklahoma caused the death of a 76-year-old Oklahoma City man, and three other deaths are thought to be linked to recent high temperatures, state medical officials said.

The man, who wasn't immediately identified, was discovered Monday in a home on the city's northeast side, said Kevin Rowland, chief investigator for the state Medical Examiner's Office.

"He had an air conditioner, but it was broken and the house was extremely hot," Rowland said.

Rowland said autopsies are being performed in Oklahoma City on two other people who likely died from heat-related injuries, although details on those victims weren't immediately available. A third heat-related death was being investigated in Tulsa, Rowland said.