RED DEER, Alta. -- Alberta's police watchdog says a man killed by the RCMP was shot while he was driving a front-end loader and the machine kept running after the suspect was spotted slumped in the seat.

The Alberta Serious Incident Response Team says in a news release that police, who were pursuing the suspect on suspicion of sex assault and attempted murder, fired shots at the loader after it hit a police vehicle on Christmas Day in a Red Deer industrial park.

The release says the loader kept rolling forward into a field, then began moving in circles.

"Other RCMP members who followed the front-end loader into the field were able to get close enough to see the man slumped over in the seat and no longer controlling the front-end loader," the release says.

"The front-end loader continued into a wooded area and travelled for approximately 800 metres until it became lodged against a tree."

Officers climbed into the loader and turned it off, the release continues. It says the 37-year-old man was unresponsive and bleeding in the driver's seat and he was later pronounced dead at the scene.

RCMP Insp. Gibson Glavin told reporters in Edmonton on Saturday the loader did a lot of damage before it was finally stopped.

Police say no officers or members of the public were hurt during the crashes.

The man, who ASIRT says was known to police, was a suspect in the sexual assault of a 47-year-old woman and the attempted murder of a 20-year-old man in the Red Deer early on Christmas morning.

ASIRT says officers spotted the suspect before noon in a stolen vehicle in the community of Sylvan Lake and tried to stop him, but that he reversed as hit a police vehicle and got away.

An hour-and-a-half later, officers spotted the vehicle in an industrial area and saw a man near a front-end loader. He got in and drove it through a fence and onto a highway, smashing several vehicles along the way.

Police followed and at some point, ASIRT says, the loader hit one of the police vehicles. The officer got out and fired, and another officer opened fire, too.

Both officers fired "several shots" the ASIRT release says.

Police say the man knew the victims of the alleged sex assault and attempted murder, and police say they won't release the identity of the man who was shot in order to protect their privacy.

"The man had been trying to protect the female from the original assault," Glavin explained.

ASIRT has taken over the investigation into the death.

RCMP are still investigating the other events that led to the final confrontation including the allegations of sex assault, attempted murder and theft of the loader.

Both the RCMP and ASIRT are seeking witnesses for their investigations.