The fatalities included two South Koreans and one Indonesian, Yonhap reported. Five survivors, three Vietnamese and two Indonesian crew members, were reported to be safe.
President Yoon Suk Yeol was briefed about the incident on Monday morning and ordered the oceans and fisheries minister and the head of the coast guard to deploy all available personnel and equipment to conduct a rescue, his office said.
The 35-ton fishing boat had capsized near Gunsan city in North Jeolla Province at around 7:36 a.m., Yonhap reported earlier, prompting a helicopter and a patrol vessel to be launched.