A Japanese tanker collided with a Panamanian-registered freighter in the Pacific Ocean off Shizuoka Prefecture early Saturday morning, Japan Coast Guard officials said.
The 411-ton Eiwa Maru, loaded with liquid chemicals, hit the 53,103-ton Ever Reward about 19 km off the town of Minamiizu in the prefecture at 3:08 a.m., the officials said.
Skipper Kazuyoshi Yoshimoto, 60, and three other crew members from the Eiwa Maru were rescued from a life raft by another ship nearby, according to the officials. The four are said to have suffered minor injuries.
The Eiwa Maru is based in Kurahashi town in Hiroshima Prefecture.
The Japanese ship sank around 10:15 a.m., the coast guard officials said, after drifting for some time with only about 5 meters of its bow above water.
Chemical odors have since been detected in the area around the collision site.
The officials suspect the smells stem from xylene spilled from the tanker.
Xylene is a colorless chemical liquid used to make synthetic resin. The Eiwa Maru was carrying some 500 tons of the chemical and was heading from Kashima Port in Ibaraki Prefecture to Nagoya Port.
The Panamanian-registered ship was on its way from Tokyo Port to Shimizu Port in Shizuoka Prefecture and continued its voyage, according to the coast guard officials.
The weather was fine and no restrictions on visibility were reported at the time of the accident. Two patrol boats have been sent to the site to look into the cause of the accident, the officials said.