Portsmouth Public Schools and other districts went on lockdown Thursday morning after police received messages about active shooters.

The New Hampshire Department of Safety reported that multiple state agencies are investigating the calls in districts around the state.

"At this time, these reports are believed to be a hoax. However, all threats will be taken seriously until such time as their validity is determined. Everyone is encouraged to report any suspicious activity to their local law enforcement agency," the Department said in a statement.

Gov. Chris Sununu reiterated in a statement that the threats are all hoaxes.

"However, all threats will be taken seriously until such time as their validity is determined. All state agencies are coordinating in this response, and we remain on top of this situation. We would like to thank all local partners for their diligence in responding across the state," Sununu said.

A Sweep of Portsmouth Schools

According to a message from superintendent Dr. Zach McLaughlin, all schools in the district were placed on lockdown, and police presence increased after Portsmouth Police received a call about an active shooter at Portsmouth High School.

A sweep of all schools was completed and operations returned to normal, according to a message from Portsmouth Police Chief Mark Westport.

An active shooter threat made against Dover High School also turned out to be a hoax, according to Dover Police.

"The Dover Police Department worked with school administration to ensure the safety of the school. Additionally, members of the police department made in person notifications to all other schools (both public and private) in the city, informing them of the hoax," the department said in a statement.

Manchester Police reported that other false active shooter calls are being reported around the state, but there are no credible threats.

Ten Maine police departments received active shooter threats about public schools in November, all of which turned out to be hoaxes. Similar threats were called into New Jersey schools in October.

This is a breaking story. Check back for additional details.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNH

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