A sign stating “Exceptional Measure: Entry forbidden to Unauthorized People and Vehicles” is erected at an entrance to Beichuan County, May 24, 2008. Due to the risk of secondary natural disasters such as landslips or mud and rock slides, and the need to avoid interfering with damaged buildings, Disaster Relief Command in Mianyang City has decided to seal Beichuan from unauthorized entry. Special Restrictions were put in place on May 21 with the approval of the Sichuan Provincial Government.