A St. Louis, Mo., man faces a homicide charge in the fatal attack of a co-worker with a circular saw at a River Falls-area job site.

Miguel Angel Franco Navarro, 24, is charged with first-degree intentional homicide and one count of mayhem in the Aug. 6, 2018, attack that left 37-year-old Israel Valles-Flores dead, according to a criminal complaint filed Thursday in Pierce County.

According to the complaint:

Navarro and Valles-Flores were part of a four-man crew replacing shingles on a roof of a home on County Road FF just outside the city of River Falls. Witnesses told authorities Navarro cut Valles-Flores with a circular saw, causing Valles-Flores to fall backwards onto the garage roof where Navarro continued to cut him. The two other co-workers reportedly jumped off the roof and hid until police arrived.

READ MORE: Update: Motorcycle passenger dies in 3-vehicle crash at highways 316 and 61Village dissatisfied with former deputy's final plea sentence

There was no apparent argument leading up to the attack, though in a recorded jail call Miguel allegedly said he had been teased and was not getting paid, as well as that he thought he had been possibly drugged to work more "and didn't feel right," according to the complaint.

Valles-Flores died of his injuries on the garage roof. He sustained 10 sharp force injuries across his face, neck, back and lower and upper extremities, as well as a transection of the jugular vein and carotid artery, according to a provisional autopsy.

A first-degree intentional homicide conviction carries a life sentence. The mayhem charge carries a maximum sentence of 40 years in prison and a $100,000 fine.

Navarro was being held Thursday in Pierce County Jail on $500,000 cash bond.