( CNN ) -- The Australian cruiser met the disguised German vessel in the waters off western Australia two years after the two became enemies in World War II . The gun turret of the Sydney II was discovered with the rest of the vessel in March 2008 . The Australian ship approached , trying to determine whether the vessel was friendly . It was n't . What resulted was Australia 's worst naval disaster : the sinking of the Australian ship and the loss of its entire crew of 645 . The wreckage was n't found until last year , leading to decades of conspiracy theories about what actually happened . On Wednesday a long-awaited report on the sinking of the Sydney II ended the mystery that began when it met its fate , November 19 , 1941 . Made to look like a cargo ship , the German vessel was in fact a military raider that fired on the Australians when they got close . The Sydney fired back and , in the end , both ships went down . More than 300 of the sailors on board the German vessel , the Kormoran , survived . But because they were the only witnesses to the disaster , some doubted their accounts , leading to various theories about the real fate of the Sydney . After the wrecks of both ships were located in March 2008 , an Australian commission began an inquiry to formally close the book on the loss of the Sydney . The results confirm the accounts provided by the German sailors . They said the Sydney closed in on the Kormoran until it was parallel with the German ship , little more than 1,000 yards away . `` Sydney obviously thought the ship was friendly and was taken by surprise when , after she asked what she believed to be ( a friendly ship ) to give her secret call sign , the response was a number of salvos that destroyed Sydney 's bridge and amidships superstructure and a torpedo strike that crippled the ship and her forward guns , '' the report said . The Sydney had given up its tactical advantage of speed and armaments by getting so close to an unknown vessel , the report said . While that may have been an error of judgment by the Australian captain , Joseph Burnett , the report accepted that other factors -- which may never be known -- influenced his decision . `` It can never be known what matters were , in fact , operating in Capt . Burnett 's mind when he decided to take the Sydney to the position described . Nor can it be known what advice , if any , he sought from or was given by other officers on the bridge , '' the report says . `` What is known , however , is that , in trying to identify the sighted ship , Capt . Burnett was performing his duty as a commanding officer . '' The German ship inflicted `` enormous damage '' on the Sydney during a battle that is believed to have lasted about 35 minutes and left 70 percent of the Sydney 's crew dead or incapacitated , said Cmdr . Jack Rush , the lawyer who presented the evidence gathered by investigators to a commission of inquiry led by a retired judge . It is likely that Burnett , the navigator , and all of the Sydney 's senior officers were taken out on the first salvo , Rush said . A torpedo tore into the Sydney 's bow , flooding the forward end of the ship , while the Kormoran fired an estimated 87 rounds from its 15-cm ( 5.9-inch ) guns into the Australian cruiser . The Sydney limped away and sank sometime between 2 hours to 4 1/2 hours later , Rush said . During the battle , however , the Kormoran itself was hit by an Australian shell that damaged its engines and set the vessel ablaze . With hundreds of mines aboard , its captain ordered the crew to abandon ship , fearing the fire would set those off . Charges were set and the ship was scuttled . About 80 of the Kormoran 's crew of nearly 400 were lost . A search began only five days after the battle , when the Sydney failed to return to port in Fremantle . And an 11-day delay by Australia 's government in announcing the ship 's loss fueled what a 1999 parliamentary report called `` a proliferation of theories '' about the fate of the crew -- that the ship was actually sunk by a Japanese submarine , that survivors were machine-gunned in the water or that the government hid bodies after they washed up on the beach . The commission thoroughly investigated all the theories and speculations surrounding the disaster and found no substance in any of them , said Terence Cole , president of the commission . Researchers found the Sydney 's wreckage in the Indian Ocean , about 207 km ( 128 miles ) off Australia 's west coast . The commission was appointed in May 2008 and began its inquiry in January . `` For a long time our nation has struggled to understand how our greatest maritime disaster occurred . The unanswered questions have haunted the families of those brave sailors and airman that never came home , '' Air Chief Marshal Angus Houston , the chief of the Australian Defence Force , said in a written statement .
Finding : Sydney 's captain , senior officers likely to have died in first salvo . Sinking of Sydney II and loss of crew of 645 was Australia 's worst naval disaster . German vessel , the Kormoran , was made to look like a cargo ship . Both ships went down ; more than 300 on Kormoran survived ; wrecks found last year .