All Maine Bureau of Motor Vehicle branch offices are open to the public today following a Tuesday closure prompted by a “serious threat.”

The branches were closed to walk-in customers because of a threat “that was specific enough that we felt it best to close the branches to walk-in customers,” Emily Cook, spokeswoman for the Maine Secretary of State’s Office said in a statement.

The 13 branch offices continued to serve those with scheduled appointments on Tuesday and fully reopened Wednesday.

Capitol Police, Maine State Police and the Bureau of Motor Vehicles’ Enforcement Division are investigating. No arrests had been made as of Wednesday morning, Cook confirmed.