At least four people are confirmed dead and nearly 300 are missing after a passenger ferry carrying 476 people—including more than 300 high school students and their teachers—sank off South Korea's coast this morning, reports Yonhap. Divers, helicopters, and dozens of boats scrambled to pluck people from the water after the boat sent a distress call and sank while on its way to the island of Jeju, reports the AP, in what it calls a "frantic, hours-long rescue by dozens of ships and helicopters." Yonhap reports that fears are now mounting that many of the missing are trapped inside; it took divers hours to get into the ship, but the first three areas they searched were free of bodies. The water temp is reportedly about 54 degrees Fahrenheit, cold enough for hypothermia to start to set in within about 90 minutes.
Survivors described terrifying scenes inside the ferry after it apparently hit something and began to tilt severely, trapping people inside as water rushed in. One surviving passenger tells CNN that he tried to save others but there were some he couldn't get to in time. "I stayed till the last to rescue people at the hall," he says. "But the water was coming in so fast (that) some didn't make it out." Rescue teams were able to pull some survivors through windows before it submerged. Saying she was "truly devastated," President Park Geun-hye spurred rescuers on. "There is not much time left before sunset," she said. "Please make the best efforts to rescue even one more person."