( CNN ) -- Eight people were injured in an explosion at a naval weapons station 's boathouse in New Jersey Tuesday morning , the U.S. Navy said . The blast at Naval Weapons Station Earle happened at about 9 a.m. while personnel were performing maintenance on a vessel , the Navy said in a news release . Seven sailors and a Department of Defense civilian firefighter were injured . Though all eight were taken to hospitals , none had life-threatening injuries . By Tuesday night , the Navy said seven of the eight had been treated and released after suffering minor injuries , mostly from smoke inhalation . One sailor remained hospitalized and underwent surgery for a broken arm , the Navy said . `` The situation is stabilized . We are investigating the accident , '' Navy spokesman Mike Brady said . Information on what exploded was n't immediately available . Authorities are investigating what caused the blast , the Navy said . The workers ' names were not immediately released . `` The damage from the explosion was contained within the boathouse area , '' the Navy 's release said . Naval Weapons Station Earle , which supplies ordnance to the Navy 's Atlantic fleet carrier and other groups , is south of Middletown , New Jersey . CNN 's Chris Lawrence contributed to this report .
NEW : One sailor remains hospitalized , the Navy says . NEW : Seven people have been treated and released . A blast occurs as maintenance work is done on a vessel at a weapons station , the Navy says . Damage is contained in boathouse area , the Navy says .