ANCHORAGE, Alaska — One person was killed and three were injured by a landslide that prompted a mandatory evacuation in the Alaska city of Ketchikan, authorities said.

Three people were transported to Ketchikan Medical Center following the landslide, which struck around 4 p.m. Sunday and damaged homes and infrastructure, the Ketchikan Gateway Borough and City of Ketchikan said in a joint statement Sunday.

Alaska Gov. Mike Dunleavy declared an emergency for Ketchikan, while Borough Mayor…