Officials in Maryland say smoke from the wildfire in the Great Dismal Swamp National Wildlife Refuge is reaching the state. The refuge is located in southeastern Virginia and northeastern North Carolina. Emergency officials in Annapolis say they’ve received multiple calls about a strong smoke odor, and Baltimore officials say smoke clouds have reached the city.

According to WAMU, the brush fire, which was ignited by a bolt of lightening on August 4, has burned nearly 5,600 acres. The fire is thought to be the largest in the refuge’s history, with smoke visible from outer space.

Residents should keep their windows and doors closed, and anyone with respiratory illnesses affected by smoke fumes are being told to seek medical attention.