File photo of a ferry in Penobscot Bay carrying vehicles and passengers from Islesboro to Lincolnville.

Maine Transportation Commissioner David Bernhardt has authorized the suspension of ferry service to Islesboro if alleged threats against ferry service employees continue.

The alleged threats come in the wake of a fare hike by the Maine State Ferry Service that would cause a roundtrip ticket for Islesboro residents to nearly double.

Bernhardt sent the warning in an April 19 letter addressed to Islesboro Town Manager Janet Anderson.

The letter alleges that passengers on the ferry, which shuttles Islesboro residents to the Lincolnville terminal, have tried to engage staff and crews with their “displeasure about the new rate structure,” Bernhardt wrote.

Some of this displeasure has taken the form of threats, according to the letter. Examples cited by Bernhardt include “a post to the Islesboro Facebook page suggesting customers fire bomb the ferry service” and a comment made to a crew member about “needing to wear a bulletproof vest.”

“For the residents and customers of the Islesboro ferry to be harassing, intimidating and threatening the dedicated employees that serve them is completely unacceptable, and this type of conduct should embarrass the community of Islesboro,” Bernhardt wrote.

If necessary, the Maine State Ferry Service will be coordinating additional security measures with the Waldo County Sheriff’s Office at the Lincolnville and Islesboro terminals.

Service would only be suspended if the alleged threats continue. The letter describes the length of a possible suspension as “until such a time as we are assured that it is safe to resume service.”

The town of Islesboro is working to file an appeal to the rate hike by a May 17 deadline. The town’s board of selectmen is working on a letter to the DOT to protest the overall rate hike, as well as the suspension of service warning, according to Anderson.

Prior to the letter being sent, Anderson said the Maine State Ferry Service Manager Mark Higgins called to express concern about the alleged threats. Anderson told Higgins that the ferry service needed “to do what you have to do.”

“We certainly don’t condone that kind of action and I’m sure [the threats] were just in jest,” Anderson said. “But I’m aware these are serious concerns.”

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