Divers trying to recover the remains of 118 sailors from the wreck of the Kursk submarine have cut the first man-sized hole in the vessel, a Russian navy spokesman said.
Igor Dygalo said the divers were firing pressurized water into the sub to clear away debris that could hamper their work.
A camera will assess conditions inside the Kursk, which was ripped open by two explosions in August, before any decision would be made on sending men inside, Dygalo said.
Divers must pierce seven holes to reach all parts of the submarine where remains of crew members might be found.