SEOUL South Korea has recovered from the sea part of a rocket used in North Korea's failed attempt to launch its first military satellite last month, the Joint Chiefs of Staff said on Friday.

The part was salvaged on Thursday evening, the military said, adding a search was continuing for additional objects from what the North claimed was a space launch vehicle.

On May 31, North Korea attempted to launch its first spy satellite into space, although it ended in failure with the booster and payload plunging into the sea.

South Korea has been conducting salvage operations after the rocket plunged into waters off the west coast island of Eocheongdo.

Photographs released by the South Korean military showed a large cylindrical object.

"The salvaged object will be thoroughly analysed by expert organisations including the Agency for Defense Development," the military said in a statement.

(Reporting by Soo-hyang Choi; Editing by Ed Davies)