North Korea sent troop reinforcements to Russia’s Kursk region early this month, South Korea’s intelligence assessed on Thursday, after the DPRK contingent suffered heavy losses fighting Ukrainian forces.

In a notice to media, Seoul’s National Intelligence Service (NIS) said North Korean reinforcements entered combat near Kursk in the first week of February but didn’t specify how many soldiers, stating that the agency continues to assess the scale of the latest deployment.

The news follows reports about a temporary withdrawal of DPRK forces from the front lines for retraining in January after heavy losses, and their reintroductionto battle zones this