A Russian dredging vessel has rammed into rocks off the south-western coast of Sakhalin Island, trapping 20 sailors on board, a local emergencies official said on Wednesday.

The incident reportedly took place late on Tuesday near the island of Moneron, some 40 kilometers (25 miles) from Sakhalin.

One sailor is missing following the incident, according to the local prosecutor's office,.

Seventeen of the crew members will be evacuated on Wednesday by a helicopter, the official said, adding that a rescue ship is heading to the site of the incident.

There has been no information on any possible oil leaks, he said.

YUZHNO-SAKHALINSK, September 8 (RIA Novosti)