More than 500 rescue divers struggled on Thursday to find any passengers who might still be alive trapped inside the ferry that capsized a day earlier off the southwest coast. Starting at 5 a.m., 169 boats and 29 helicopters converged on the wreck to take part in rescue operations.
But no more survivors were found as the rescue continued into the night.
Rain and winds of up to 10 m/s at one point compounded difficulties facing the rescuers, creating 1.2 m waves that lashed the wreck.
Kim Soo-hyun, head of the maritime police in the West Sea region, said the scene of the accident was notorious for being home to the "second-fastest currents" in Korea, which travel at 4.6 knots or around 8.5 km/h.
A spokesman for the Korea Meteorological Administration said, "Such weather rocks rescue boats severely, and divers' safety ropes can tear, which makes things very difficult."
Divers tried to enter the capsized ferry every six hours when the currents calm down between low and high tides but failed to get inside the ferry. "The currents are just too strong to even get near the ferry," one diver said. "We're just circling the ferry."
Three divers were swept away by the currents as they risked their lives trying to approach the ferry at around 3 p.m. They were rescued by a fishing boat 20 minutes later.
The families of missing passengers protested angrily as rescue efforts yielded scant results. An official at the government's disaster management taskforce said, "Although the results so far have been less than satisfactory, rescue workers are risking their lives at the scene."
Maritime police said they would attempt to salvage the ferry once three crane barges arrive at the scene on Friday.