ELLSWORTH, Wis. — Investigators allege teasing led to a roofer killing a co-worker with a circular saw in western Wisconsin.

Miguel Navarro, 24, of St. Louis was charged Thursday in Pierce County court with first-degree intentional homicide and mayhem, both felonies, in the death of Israel Valles-Flores, 37, also of St. Louis.

According to the complaint, Navarro was seen attacking Valles-Flores with a circular saw while on a home’s roof near River Falls. The victim ended up on the garage roof, where he died of his injuries. A witness said Navarro continued cutting Valles-Flores after the victim fell backward on to the garage roof, according to the complaint.

A witness said Valles-Flores handed the saw to Navarro, who immediately cut into the victim’s neck. A bloody circular saw was found on the ground.

During a recorded jail call, Navarro said the other workers, including Valles-Flores, were teasing him because he wasn’t feeling well after having sex. There was no apparent argument before the attack.

Navarro was mad about being teased and “he was getting really mad inside,” the complaint said. He also thought he was being drugged, perhaps to work more, and was not getting paid, according to the complaint.

After the attack, a witness heard Navarro calling for him as he ran away and was afraid Navarro was going to hurt him, the complaint said.

An autopsy found Valles-Flores had 10 sharp force injuries, including to his face, neck and back. The jugular vein and carotid artery in his neck were both cut.

A court hearing is scheduled Monday for Navarro, who remains in jail. Online court records do not list a defense attorney who could speak on his behalf.