Authorities say they are investigating online threats to kill Jewish and Muslim students at a South Carolina high school.

Spartanburg School District 5 said in a news release that a Byrnes High School student reported the threats Friday evening. The threats said Byrnes High would be attacked Tuesday and included pictures of a person in a gas mask and a knife with a swastika on the handle.

Superintendent Scott Turner says Spartanburg County deputies are patrolling the school the holiday weekend, and there will be security sweeps and extra officers on hand when school returns Tuesday.

The sheriff’s office says it is investigating the threats, but no arrests have been made.

Byrnes High has about 2,300 students and is one of the largest high schools in South Carolina.

(AP)