LISBON — Two threatening messages discovered on two different days caused Lisbon High School officials to close school early Wednesday, according to Principal Susan Magee.

A letter from Magee sent to parents and students at around 1 p.m. Wednesday only describes the messages as “threatening,” and states that local and state police are investigating.

Wednesday’s early dismissal comes after an initial alert Magee sent to parents on Tuesday about a threat found in a bathroom.

Superintendent Richard Green said he doesn’t know if the two threats are related. Green said the school wasn’t evacuated Tuesday.

Lisbon police posted on social media Tuesday afternoon that there was “graffiti observed inside the school making reference to a terrorizing matter.”

The post notes that police and school administrators investigated, “and have at this time found the comment to be without any validity or substance.”

“To alleviate some anxieties, over the next few days, we will be increasing the amount of police presence in and around the building,” Magee wrote on Tuesday.

Further details regarding Tuesday’s threat, as well as the threat discovered Wednesday, were unavailable while an investigation continues, Green said.

“We’re working with both our local and state police to determine where these are coming from and if or how much of a threat they pose,” Green said.

Regarding Wednesday’s evacuation that was mandated by state police, Green said: “In my opinion staff did a really good job calming kids if anyone had any questions.”

Green said he didn’t know yet if the high school will be closed additional days but said he expects to have more information from the state police soon to help determine the next steps. That information will be sent to parents, he said.

“For students and staff, safety is our top priority and we did early dismissal out of an abundance of caution,” Green said.

As of 5 p.m. Wednesday, Green said he didn’t have any updates but expects to get more information from police soon and update families later on Wednesday.

Anyone with any information about the threats should contact Magee, who said she will provide more information later today.

Lisbon’s anonymous tip line can be accessed via lisbonme.org/police.