Authorities say high temperatures and strong winds have worsened conditions, driving the flames closer to homes.
Six wildfires are currently active in León, with two considered to pose a major risk due to their proximity to populated areas.
In Yeres, around thirty people were moved as the fire also approached the UNESCO World Heritage site of Las Médulas.
The regional government has declared a level 2 alert, and almost a dozen aerial and ground teams have been deployed. The fire began on Saturday, and its cause is under investigation.
