A Minnesota man is accused of crushing his co-worker’s head with a hydraulic grapple while the pair were “f—— around” during a tree-trimming job, killing the 26-year-old.

Christopher Boone Crimmins, 34, is charged with second-degree manslaughter after allegedly operating a truck-mounted hydraulic grapple that closed on his co-worker’s head.

According to a criminal complaint filed Friday in Dakota County, Crimmins told police that he and Tyler Anthony Lynch, 26, were working together in Apple Valley on Thursday afternoon when the two started “f—— around.”

The men noticed the grapple’s shadow and Lynch’s shadow on the ground, and Crimmins allegedly began moving to grapple to make it look like it was grabbing Lynch. Crimmins was watching the shadows rather than Lynch himself, the complaint said, and didn’t realize the grapple was closing in on Lynch’s actual head until it crushed it.

Police who arrived at the scene found Lynch on the ground “with a large amount of blood around his body and a significant injury to his head,” according to the Dakota County Attorney’s Office

A witness told investigators they saw the grapple hit or pinch Lynch’s head, the complaint said. Crimmins was the only member of the crew with the commercial license to operate the machine, which the team was using to clear branches during the job.

Bail was set at $40,000 unconditional, or $20,000 with conditions, the Dakota County Attorney’s Office said Friday.

Crimmins faces up to 10 years in prison if convicted.

As of Sunday afternoon, Crimmins was not listed in Dakota County Jail records. Court records were not immediately available, and it’s unclear whether he has retained an attorney. A phone number listed for Crimmins was not immediately returned Sunday.

He’s next expected in court on Sept. 10, according to the county attorney’s office.