Some Maine schools were in a “soft” lockdown Friday due to what police say are non-specific threats that mentioned Susan Collins.

The Bangor Daily News reports Bangor High School, as well as schools in Fort Kent and Frenchville in Aroostook County, were in a soft lockdown, meaning classes resume as normal but no one can leave or enter the buildings.

School officials said the threat was sent Friday morning via email to a business in Orono, and mentioned several high schools throughout the state. One superintendent said the threat mentioned Republican Senator Susan Collins, who’s been involved this week in the senate’s impeachment trial of President Trump.

Police were on site at Bangor High School on Friday.

The threats are being investigated.