Police say a young man seriously injured in a weekend dirt bike accident in Pittston has died. The Kennebec County Sheriff’s Office says 22-year-old Michael Lund died of his injuries Tuesday at Central Maine Medical Center in Lewiston. Police initially reported that Lund was from Pittston, but later said he was actually from nearby Richmond. Police tell the Kennebec Journal, that Lund was visiting a friend on Sunday evening when he went for a ride alone on the bike. He was not wearing a helmet. Friends went looking for him when they could no longer hear the sound of the engine. They found Lund lying just off the road. The bike was not damaged. Police say the investigation is closed.