The Pentagon said Tuesday it would exhume and try to identify the remains of nearly 400 sailors and Marines killed when the USS Oklahoma sank in the bombing of Pearl Harbor. The ship capsized after being hit by nine torpedoes during the December 7, 1941 surprise attack from Japanese forces. Altogether, 429 sailors and Marines onboard were killed. Only 35 were identified in the years immediately after. Hundreds were buried as unknowns at cemeteries in Hawaii. In 1950, they were reburied as unknowns at the National Memorial Cemetery of the Pacific - also known as the Punchbowl - inside a volcanic crater in Honolulu. Scroll down for video . Casualties: The Pentagon announced Tuesday plans to exhume the bodies of some 400 sailors and Marines who were killed on the USS Oklahoma on December 7, 1941, in the Japanese assault on Pearl Harbor. Above, the ship seen capsized after the attack . Resting place: The sailors and Marines who died on board the USS Oklahoma are currently buried as unknowns in Honolulu's National Memorial Cemetery of the Pacific . Nameless: Above, a gravestone at Honolulu's National Memorial Cemetery of the Pacific, marking the resting place of seven unknown Americans who died on board the USS Oklahoma . The military is acting now, nearly 75 years after the men died, because advances in forensic science and technology as well as genealogical help from family members have made it possible to identify more remains, said Lt. Col. Melinda Morgan, a Defense POW/MIA Accounting Agency spokeswoman. The move is apparently a part of a new Pentagon policy on disinterring the remains of unknown troops. According to the new policy, bodies may be exhumed from Punchbowl or any other permanent American military cemeteries - but they can not be removed from any U.S. Navy vessel that is being used as a national memorial, like the USS Arizona which remains sunk and on display in Honolulu. The bodies of Marines and sailors lost at sea do not apply to this new effort. In order to disinter these large groups, researchers must also prove that they can identify at least 60 per cent of the group with supplied family DNA samples, medical and dental records. 'The secretary of defense and I will work tirelessly to ensure your loved one's remains will be recovered, identified, and returned to you as expeditiously as possible, and we will do so with dignity, respect and care,' Deputy Secretary of Defense Bob Work said in a statement. 'While not all families will receive an individual identification, we will strive to provide resolution to as many families as possible.' Officials plan to begin the work in three to six weeks, Morgan said. They aim to identify the remains of up to 388 servicemen within five years. In 2003, the military disinterred one casket at the National Memorial Cemetery of the Pacific based on information provided by Ray Emory, a Pearl Harbor survivor who has spent years doggedly scouring documents. Loss of life: The USS Oklahoma was hit with nine torpedoes in the assault, which caused the boat to tip over and capsize - trapping many inside . Revenge: The Oklahoma pictured above before the attack. Overall, more than 2,000 Americans died in the surprise attack on December 7, 1941 which sparked the entrance of the U.S. into World War II . Watery grave: The capsized deck of the Oklahoma is seen on May 24, 1943  - two and a half years after the attack . Rescue: After the ship capsized, survivors worked hard in an attempt to rescue some of those trapped inside . Many remains were comingled when buried, and the military was able to identify five servicemen from that casket. But the coffin also contained the remains of up to 100 others who haven't been identified. 'It's something I looked forward to for a long time,' Emory told CNN about Tuesday's news. The Pentagon started notifying families on Tuesday about the plans to disinter and identify the bodies. If a body is identified, the family will be notified and the sailor or Marine's remains returned to them for a full military burial. Bob valley of Escanaba, Michigan was one of the first to hear about the plans. Escanaba told the Honolulu Star Advertiser that he received a call from the Navy Casualty Office, about his brother Lowell who died at the age of 19 on board the Oklahoma. Lowell worked in the boiler room on the port side of the ship, which was hit by Japanese torpedos. The onslaught caused the ship to roll over and capsize - trapping much of the crew inside. 'I can hardly talk,' Valley, 82, said of receiving the call. 'Families want some kind of closure.' Valley says his parents received a telegram right before Christmas 1941, saying Lowell was missing, and then another two months later saying he had died. 'And that's all they ever got. They never got any information about Punchbowl cemetery. They never heard of a Punchbowl cemetery,' Valley said. Valley said his parents tried hard to get information on where their son was buried, even seeking the help of a local congressmen. If identified, Valley says he already has a burial plot ready for his brother.
The Pentagon announced Tuesday plans to identify the remains of hundreds of sailors and soldiers killed on board the USS Oklahoma . The USS Oklahoma sank during the December 7, 1941 Japanese assault on Pearl Harbor, the American military base and port . The attack on Pearl Harbor resulted in the death of over 2,000 Americans and marked the United States' entrance into World War II .