The U.S. Postal Service is removing mailboxes in several American cities as the threat of violence in state capitols surrounding President-elect Joe Biden’s Wednesday inauguration continues to escalate. Explosive devices can be placed inside mailboxes to cause serious injury or death to anyone passing by, although the USPS is describing it simply “as a security measure to protect the mail and the public.”

“Due to reports of possible demonstrations beginning this weekend, out of an abundance of caution for the safety of our employees and to prevent damage to postal equipment, a number of blue collection boxes near the capitol are being temporarily removed from service,” USPS spokesperson Bob Sheehan told Madison, Wisconsin’s CBS 58. Other states affected include Colorado, Nevada, Minnesota, South Dakota, Oregon, Arizona, Montana, and New Mexico.