North Korea has claimed an accident occurred when it planned to send up its first space satellite which crashed into the sea.

Pyongyang announced earlier it planned to launch a satellite by 11 June to monitor US military activities, reports BBC.

The nation said it will attempt to send the satellite once again in future.

South Korea's Joint Chiefs of Staff (JCS) said it detected the launch from Tongchang-ri on the North's west coast at 6:29 a.m. and the projectile fell into waters some 200 kilometers west of the South's southwestern island of Eocheong following its flight over the waters far west of the border island of Baengnyeong, reports Yonhap news agency.

The South Korean military identified an apparent part of the North's vehicle and retrieved it, the JCS added.

The part could shed light on the makeup of the rocket and the North's technological progress, observers said.