Seoul , South Korea ( CNN ) -- A diver searching the sunken Sewol ferry died Tuesday , according to South Korea 's Government Rescue Headquarters . `` A civilian diver , Lee , lost the communication line at 25 meters under the sea five minutes into his first dive , '' spokesman Koh Myung-suk said . `` By the time his colleagues went to save him , Lee was unconscious and unable to breathe by himself , '' Koh said . Lee , whose full name was not provided , was helicoptered to a hospital where he was pronounced dead , the spokesman added . Park In-ho , head of the hospital where Lee died , said the diver 's blood was tested and appeared normal except for high potassium . His chest X-ray also showed no sign of irregularity . Not including the diver , the death toll in the ferry disaster has risen to 264 , with 38 people still missing , the government reported . Over the weekend , South Korean President Park Geun-hye visited the port where the rescue operation is based to console families and encourage divers . Nearly 130 divers are combing the ship , looking for the remaining missing bodies . The search-and-rescue operation has turned into a grueling recovery of corpses . No one has been found alive since the ferry sank April 16 with a passenger load largely made up of high school students on a field trip . The work has become even more difficult because divers have faced closed cabin doors blocked by debris . Corralling the debris has been difficult for search teams . Mattresses and clothing from the ship have been found up to 9 miles ( 15 km ) away from the accident site , said Park Seung-ki , a spokesman for the rescue operation . Large stow and trawler nets will be set up around the sunken ship to catch items that may float away , he said . At the same time , some three dozen ships will be clearing an oil spill from the ferry , which is threatening the livelihood of the local fishermen . The ferry sank en route from Incheon to the resort island of Jeju , off the nation 's southwestern coast . CNN 's Stella Kim reported from Seoul ; Ed Payne wrote from Atlanta .
Nearly 130 divers are aboard the sunken ship . Not counting the diver , the disaster 's death toll rises to 17 . More than three dozen people remain missing . The South Korean government supports families over the weekend .