THOMPSON, Man. -- A plane that crashed in northern Manitoba, sending eight people to hospital, may have had the wrong fuel.

The Navajo Chieftain aircraft operated by Keystone Air, crashed just short of the runway at Thompson Airport on Tuesday evening.

Keystone Air president Cliff Arlt says the company has learned the aircraft may have been fuelled with jet fuel in error, rather than Avgas, as would have been required for the Navajo.

The company says all six passengers apparently got off the plane on their own, but there was no more information on their condition.

The two pilots were also hurt, but none of their injuries are believed to be life-threatening.

The Transportation Safety Board is investigating.

TSB spokesman Chris Krepski said Tuesday that it was too early to speculate on what caused the crash, saying weather conditions and other factors would be part of the investigation.

This is the second crash involving a Keystone Air plane in recent years.

Four people, including the pilot, were killed and a fifth was seriously injured when a Keystone Air plane hit the icy surface of a lake at a remote reserve about 400 km north of Dryden, Ont., in 2012.

The TSB later found that poor weather, ice on the wings and the pilot's inexperience landing in icy conditions contributed to the crash.

Keystone Air, which operates eight aircraft out of its headquarters in St. Andrews, Man., says it offers cargo, passenger, and executive transportation throughout North America.