More than 5,000 high school students and parents in the Gardner school district in Massachusetts received threatening and racist emails over the weekend through the district vendor “plusportals.com.”

Recipients received two emails that appeared to be from a school account. The messages contained a “threat against a school,” graphic images, and “racial phrases,” NBC News reports. 

Following the threats, the Gardner Police Department, which was first notified of the incident on Jan. 23 at around 12:35 a.m., searched the school and found no valid threats, which an email alleged would be carried out on Sunday.

“The Gardner Police Department has checked the schools to ensure they were secure and no threats were located at this time,” police said in a statement.

“The police department is working with the school department and the city’s technology department to investigate this matter and will continue to do our best to ensure the students and staff’s safety.”

While specifics about the emails were not released, the NY Daily News noted that Gardner is a predominately white city, but over the years, the area has experienced a growth in its Hispanic population.

A criminal investigation has been launched by the Gardner Police Department, and the school later issued an apology over the emails.

“Unfortunately, many students and parents are reporting that they received a very inappropriate email last night, appearing to be sent from a school email account. We want to apologize for the graphic content of this email,” the statement read via a Facebook post.

“We are working closely with the Gardner Police Department to investigate this and to determine the origin of the email. Again, our apologies, and we will keep you updated as more information becomes available.”

Virtual and in-person sessions with administrators and counselors were then made available for the students as a result of the incident.

school classroom Stock photo of an empty classroom. Photo: Rodin Eckenroth/Getty Images