A Norwegian man has been arrested for allegedly making violent threats against Portland police officers on Wednesday.

Espen Brungodt, 28, was taken into custody by the FBI and Portland police at the Residence Inn on Fore Street at about 1 p.m. on Wednesday.

Emails containing threats against Portland police officers were reportedly sent to the Portland Police Department and two employees at the Portland Press Herald Wednesday morning.

According to the Press Herald, the email was titled “I am going to kill more police.” It reportedly said the sender and an unknown number of partners were “getting our Sig Sauer MCX .223-caliber rifles ready.”

The email also said the Cumberland County parking garage on Newbury Street had been booby-trapped with explosives, and they would “get into position at the top of the parking garage.”

The garage, which is used by both the public and Portland police officers, was searched by K9s but no explosives were found.

Similar threats were posted on Twitter by a user who identified himself as John Mackenzie with the handle @brownclown42. The account has sent out just three tweets, all of them threatening. Twitter has since suspended the account.

Police say Brungodt entered the U.S. through Boston on July 27. They say he was traveling with family members, who apparently were unaware of the alleged threats.

Brungodt is being held at the Cumberland County Jail. He faces federal charges of transmitting threatening communications.