Officials said 28-year-old Navy Diver 1st Class James Reyher of Caldwell, Ohio, and Navy Diver 2nd Class Ryan Harris of Gladstone, Mo., died Tuesday. They were assigned to Mobile Diving and Salvage Unit 2 at Joint Expeditionary Base Little Creek-Fort Story in Virginia Beach, Va.
The two had been diving at the Aberdeen Proving Ground in northeastern Maryland. One diver was pronounced dead at the scene, the other was transported to a local hospital, where he was pronounced dead later.
Tuesday's incident at Aberdeen's Underwater Test Facility occurred less than a month after George Lazzaro Jr., a 41-year-old engineering technician, died while performing maintenance at the same site.
Kelly Luster, a spokesman for the Aberdeen Proving Ground, said Tuesday's deaths are not believed to be connected to the earlier incident. But officials said Wednesday that the test facility has been closed for all diving operations until investigations into the recent deaths are done.
The test facility, dubbed the "Super Pond," is used to conduct shock testing of vessels, submarine systems and munitions. With a bottom measuring 300 feet in diameter and a maximum depth of 150 feet, the facility also has been used in testing torpedoes, missiles, warheads, amphibious and remotely controlled vehicles, underwater gun firing and acoustics.
The sailors belonged to a unit whose salvage operations have included TWA Flight 800, Swiss Air Flight 111, the space shuttles Challenger and Columbia, and the Civil War ironclad USS Monitor.
The unit also provided damage assessments and repairs on the USS Cole and participated in humanitarian missions following Hurricane Katrina and the 2010 earthquake that struck Haiti.
Deputy Commander Capt. John Coffey said Wednesday, "Petty Officer Harris and Petty Officer Reyher were exceptional Sailors."