SEOUL, South Korea - South Korea dispatched coast guard and military rescue boats and helicopters to aid a passenger ferry carrying 476 people that was sinking off the nation's southwest coast.

There were conflicting reports on the number rescued so far. One person was reported dead and 14 injured.

A total of 324 students from Danwon High School southwest of Seoul, accompanied by 14 teachers, were on the ferry, and all were rescued, school official Kim Tae Eun told Reuters by phone. The students were on a school excursion to Jeju Island, Kim said.

Other officials put the number rescued so far at fewer than 150.

The vessel is owned and operated by Chonghaejin Marine Co., a company official said by phone, asking not to be named, citing internal policy.

YTN TV footage showed the vessel, named "Sewol," or "time and tide" in Korean, mostly submerged on its side in calm waters near the shore off Jindo Island, northwest of Jeju.

The ship may have hit rocks in heavy fog, the broadcaster said.

The 6,825-ton ferry can carry as many as 921 passengers and 130 vehicles traveling between Incheon and Jeju, popular among honeymooners and holiday-makers.

The ferry left Incheon two hours late due to fog, Yonhap News reported. It was also carrying 120 cars, the agency said.