One sailor has died and another has been seriously injured while training in a swimming pool at Joint Expeditionary Base Little Creek-Fort Story, officials say.

The two were found unresponsive Friday at the bottom of the base's Combat Swimmer Training Facility, which personnel use for fitness training. Both were assigned to Naval Special Warfare Group Two, which contains SEAL teams.

The sailors were taken to a civilian hospital, where one was pronounced dead. The second service member was listed in critical condition.

Base officials did not release the sailors' names pending notification of next of kin. Group Two Commander Capt. Pete Vasely said an investigation is ongoing.