Divers Saturday tried to reach the wreck of a passenger boat that sank two days earlier while rescuers kept up their search for 24 people listed as missing in the accident. At least 46 passengers of the MV Catalyn B were rescued after it sank off the coast of Cavite when it collided with fishing boat Natalya at dawn Thursday. The MV Catayn B was on its way to Mindoro while the Natalya was bound for Navotas from the North Harbor when the sea mishap happened. Authorities have so far retrieved three bodies from the waters off Limbones Island in Cavite province where the collision occurred. Coast Guard commandant Admiral Wilfredo Tamayo said in a radio interview his agency's search for survivors yielded nothing more. This gave rise to speculations that the missing passengers were trapped inside the wooden-hulled ferry. He said six ships - three each from the Coast Guard and Navy – and a Coast Guard aircraft, found only debris in the vicinity of the collision site. “We have to really explore deep-sea diving as another possibility,” he said. He said the Navy and Coast Guard were to start Saturday shifting efforts from search-and-rescue to search and retrieval. The coast guard divers were to use specialist deep-sea equipment to enable them to reach the wreck of Catalyn B, a flimsy, wooden-hulled vessel, that now lies in 220 feet of water. “They are now descending with the search equipment so they can properly locate the wreckage underneath and hopefully conduct the diving operations and find out the condition of the vessel,” Tamayo said. He said that while the coast guard knew where the Catalyn B went down, they could not be certain of its final resting place. Officials said they feared the bodies of the missing may be trapped inside the boat, but surveillance aircraft and rescue ships were still combing the waters off Manila Bay in search of any survivors. Navy spokesman Lt. Col. Edgard Arevalo said they fanned out further from the scene of the incident early Saturday to look for possible survivors. “We started out with search-and-rescue operations but it has been days since the incident, and the chances of finding survivors grow smaller. It hurts to say this, but we are now on search-and-retrieval mode,” Arevalo lamented. Tamayo said their only hope now is that fishermen or residents in nearby islands may have found and taken in some survivors.