Three people were killed and two remain missing after a fishing boat with 14 people onboard collided Friday with a cargo vessel off South Korea's southern coast, authorities said.

The nearly 10-ton fishing boat sank 80 kilometers (nearly 50 miles) from Yokji Island after running into a 3,000-ton cargo ship around 5 am local time, according to South Korean Coast Guard sources, quoted by Yonhap news agency.

Two sailors were found dead and a third person who was sent to a hospital in critical condition also died, the news agency said.

The remaining nine were being treated as rescue operations continue to search for the two missing fishermen, Yonhap added.