RANGELEY — The Maine Warden Service is investigating three snowmobile accidents that left four people seriously injured.

Two Massachusetts men were hospitalized with non-life threatening injuries after two accidents at 2:30 a.m. Sunday in Rangeley. Wardens say one of the men’s machines struck a parked camper trailer, and the other crashed into a clump of trees when he swerved to avoid the first machine.

In Greenville, a Lyman man suffered a serious leg injury Saturday afternoon when his snowmobile hit a 2-foot-high patch of packed ice on Moosehead Lake, launched into the air and flipped over.

And in Bradstreet Township near Jackman, a Winslow man suffered a broken arm after crashing into another snowmobiler at 11 a.m. Sunday.