( CNN ) -- Six people were hospitalized after a boat exploded at a Maryland marina , an official with the Anne Arundel County Fire Department said Monday . Six children , all of whom are 13 or younger , were injured , Lt. Jack Bell said . `` We saw that the dad was actually picking kids up and throwing them into the water , and people were just frantically scrambling to get off the boat , '' Care Corradin told CNN affiliate WJZ . Corradin said the people from the boat began to swim back to the dock . `` And there was a ton of smoke just billowing out the back , and the dad went back in and picked up all the life vests and he was throwing the life vests at the kids and the people in the water , '' Corradin said . Sgt . Brian Albert of the Maryland Natural Resources Police , which is leading the accident investigation , said two of the children were transported to the Johns Hopkins burn center . No one on the boat suffered life-threatening injuries , he said . Bell said the boat got gas at the marina , and the 32-foot vessel , with nine people aboard , stalled when it left the dock just after noon . The blast happened when the captain tried to refire the engines . The cause of the explosion at the Oak Grove Marina near Edgewater , Maryland , is unknown . The marina is about 30 minutes east of Washington on the South River .
NEW : Witness said man was throwing younger victims into the water . The witness told police that he saw a young girl being thrown in to the water. Boat had just refueled and captain was attempting to restart it . Marina is on South River in Maryland .