WASHINGTON — A couple hundred North Korean troops fighting alongside Russian forces against Ukraine have been killed or wounded during battle in the Kursk border region, a senior military official said Tuesday.

The official didn’t provide details on exactly how many have been killed, but said the North Korean forces don’t appear to be battle-hardened, which contributes to the number of casualties they’ve had. The official was providing the first significant estimate of North Korean casualties, which comes several weeks after Ukraine announced that North Korea had sent 10,000 to 12,000 troops to Russia to help it in the almost 3-year war.