A man is in critical condition after a crash involving a farm tractor in Genesee County.

It happened on North Bergen Road in the Town of Byron just after 7 p.m. Friday.

According to the Genesee County Sheriff's Office, a van rear-ended the back of the tractor carrying a manure spreader.

The van's passenger, Paul Tuttle, of Bergen, had to be cut out of the vehicle by firefighters. He was flown by Mercy flight to a Rochester area hospital with serious injuries

Deputies say the van's driver, Richard White, of Brockport, and the driver of the tractor, Kip Keller, of Byron, suffered minor injuries. 

It's still unclear what caused the crash.