( CNN ) -- Two hostages of suspected Somali pirates died after a rescue effort by the Danish navy , an operation that freed 16 other hostages , the Danish military said Tuesday . A Danish warship , the Absalon , tasked with patrolling waters near the Somali coast to ward off piracy , fired warning shots against what the navy described as a pirate `` mother ship '' that failed to stop , the military said . Military personnel then boarded the vessel and found 17 suspected pirates and 18 hostages , two of whom were critically wounded . Despite medical treatment , navy doctors were unable save their lives , the military said . An investigation into the deaths is under way . The hostages had been the original crew of what became the mother ship .
Danish navy launches operation to free hostages held by alleged Somali pirates . Two hostages die after the operation ; an investigation into the deaths is under way .