LISBON — A juvenile was arrested Wednesday night and charged with terrorizing after police said he left threatening messages at Lisbon High School earlier in the week. 

The juvenile, whose age was not listed, was taken into custody about 6:20 p.m. after an investigation that involved several local, state and federal police agencies. 

Lisbon police had been investigating since Tuesday when “a threatening word” was found in graffiti at the high school. In response, police posted extra officers at the school. 

On Wednesday, school officials were made aware of a second threatening message at the school, police said. 

“As a result of our concern and an abundance of caution,” police wrote in a statement, “the decision was made to dismiss students and staff and evacuate the building. This decision was not made as a result of any known direct threat, it was out of caution and following the district policies and procedures.” 

Lisbon police contacted the Maine State Police Bomb/Explosives Unit and briefed them on the situation. A team of state police troopers responded with bomb detection K-9s to the Lisbon High School. The Lisbon Police Department called in additional officers to assist in the investigation and the school grounds were closed Wednesday afternoon.  

The Maine State Police Explosives Unit team searched the building and advised the building was clear, police said, and no explosive devices were found. 

“During this time, other agencies were contacted to assist us in the investigation, including the Maine State Police Computer Crimes Unit, the Brunswick Police Computer Crimes, and the Androscoggin County Sheriff’s Office Computer Crimes unit,” according to Lisbon police Chief Ryan McGee.

“The United States Secret Service also assisted the Lisbon Police Department Investigators and IT representatives on the scene,” he said. “The Lisbon Police Department worked throughout the afternoon and into the evening hours with the Lisbon School Department administration to gather evidence. Numerous interviews were conducted by Lisbon investigators and several students, parents, and staff all assisted the Lisbon Police Department in the investigation.” 

The juvenile remained in custody Wednesday night, charged with terrorizing, a Class C felony. Police were not releasing further details about the investigation. 

Police said extra officers will remain at the high school through the rest of the week.