WASHINGTON » One hundred fifty years after their Civil War ironclad sank, two unknown sailors from the warship Monitor were laid to rest at Arlington National Cemetery on Friday.

"This may well be the last time we bury Navy personnel who fought in the Civil War at Arlington," Navy Secretary Ray Mabus said at a funeral service. "We do not want their sacrifice, however distant, to be unremembered."

The burial, with full military honors, came after an unsuccessful effort to identify the sailors, including forensic reconstructions of their faces last year.

The skeletal remains were discovered inside the Union warship’s gun turret after it was raised from the ocean floor off the North Caro­lina coast in 2002.

While the Joint POW/MIA Accounting Command in Hawaii spent years trying to identify the sailors, officials hope a descendant will emerge one day and provide a conclusive DNA match, a spokes­man for the National Oceanic and Atmospheric Administration said.

The burial came in advance of today’s 151st anniversary of the first battle between ironclads, the Monitor and the Confederate ship Virginia, also known as the Merrimack, in the Battle of Hampton Roads on March 9, 1862. The 41⁄2-hour duel ended in a draw.

The Monitor sank in a New Year’s Eve storm that year. The 16 sailors who died that day will be memorialized on a group marker in the cemetery.

"While naval tradition holds the site of a shipwreck as hallowed ground and a proper final resting place for sailors who perish at sea, this ceremony pays tribute not only to the two sailors being interred, but to all who died when Monitor sank so many years ago during the Civil War," Mabus said.

No trace of the other 14 missing crew members has been found, according to NOAA. The grave site sits adjacent to the memorial for NASA astronauts killed in the explosions of the Challenger and Columbia space shuttles.