The National Intelligence Service(NIS) said about five-thousand North Korean military construction units have been deployed to Russia since September for infrastructure reconstruction.

Rep. Park Sun-won of the ruling Democratic Party and Rep. Lee Seong-kweun of the main opposition People Power Party disclosed the information during a press briefing after a closed-door parliamentary audit of the NIS on Tuesday.

The agency said roughly ten-thousand North Korean troops are already stationed near the Russia–Ukraine border for guard duties, and an additional one-thousand military engineers have been assigned to mine-clearing.

The NIS said it is closely monitoring ongoing training and troop movements inside North Korea in preparation for further deployments.

The agency also noted progress in Pyongyang’s intercontinental ballistic missiles, short-range missiles and unmanned aerial vehicle programs.