A Pittston man injured in a dirt bike accident last weekend remains hospitalized in critical condition. Authorities say 22-year-old Michael Lund was hurt while out riding a dirt bike without helmet at about 7 p.m. Sunday. He was flown by helicopter to Central Maine Medical Center in Lewiston, where he remained in critical condition Monday. Police tell the Kennebec Journal, that Lund was seen riding his motorcycle alone on Troop Road, but when he didn’t return, friends went searching for him. They found him off the road. Police say the dirt bike was not damaged. Investigators are still trying to piece together what happened.