Japan's Coast Guard have found three survivors and the fourth in critical condition from a Chinese cargo ship that went missing early Wednesday south of Iriomote island in Japan's Okinawa Prefecture, an official from Chinese embassy in Tokyo said Thursday.

The Panama-registered ship "Nasco Diamondo", as well as the rest of the 25 crews aboard, who are all Chinese nationals, have not been located by Japan's Coast Guard, Jin Mingyu, consulate of the Chinese embassy told Xinhua.

The rescued crew members are being sent to Ishigaki in Okinawa for treatment, Jin said.

"Japan's Coast Guard are exerting every effort to search for the missing, and officials from the Chinese consulate in Fukuoka will arrange a visit to Ishigaki to deal with related issues," Jin added.

The ship last contacted its Chinese owner at around 7 p.m. Tuesday. Japan's Coast Guard in Naha on Okinawa island received a report saying the ship went missing some 340 kilometers south of Iriomote in the early hours Wednesday. Life raft without anyone aboard was found by passing-by ships in the nearby area at around 8:30 a.m. Wednesday.