Three people are in hospital after a small plane tried to make an emergency landing on a Yarmouth, N.S., highway Sunday afternoon.

The Yarmouth RCMP received a 911 call just before 2 p.m. concerning a plane crash.

The four-seater Cessna 172 was travelling from Greenwood to Yarmouth when it began having engine problems.

The pilot attempted to make an emergency landing in Yarmouth, said RCMP Sgt. Michel Lacroix.

"And they tried to land on a little road that leads to the wharf and they ran out of pavement and came across Highway 3 and hit a tree on the other side of the road," Lacroix said. The crash site is about 10 kilometres from Yarmouth's airport.

The plane's pilot — who had to be removed from the aircraft by emergency personnel — is reported to be in critical condition in hospital, while his two passengers are being treated for non-life threatening injuries, police said.

Lacroix said the two passengers are employees of Environment Canada who chartered the plane for a flight from Greenwood to Yarmouth. No names have been released at this point.

Police say it's too early to say what led to the emergency landing.

The plane was loaded on a flat bed truck and taken to a private hangar in Yarmouth where it will be examined by investigators from Transport Canada searching for the cause of the crash.