Responding to a recent series of typhoons that have battered North Korea, thousands of party members dispatched from the capital have arrived in South Hamgyong province to rebuild damaged towns.

Their arrival follows Kim Jong Un’s rare “open letter” to party members in Pyongyang this weekend, in which he called for volunteers to aid the response to Typhoon Maysak. The typhoon has destroyed over 1,000 dwellings on the east coast of North Korea.