Coeur d’Alene police arrested a high school student Thursday, as part of a continuing investigation into several threatening social media posts.

The Lake City High School student faces criminal charges, and possible expulsion from the school.

The student is charged in connection with three social media posts. One post threatened Lake City’s cheerleaders. Another threatening comment was posted in a group chat involving about 250 students. The third post included a photo of a Lake City student holding a rifle; the caption referred to a “threat list.”

A fourth incident remains under investigation. On Sunday evening, a social media user threatened to shoot a female student at Lake City Monday, after the student refused to send a nude photograph.

The arrest came after Lake City tightened campus security Thursday. The school banned the use of cell phones and other personal devices on campus and prohibited students from leaving campus for lunch. These restrictions, among others, remain in effect while the investigation continues.

“Due to the additional security measures we took (Thursday), students felt compelled to share enough information to enable investigators to identify the source of the most recent social media threats and make an arrest,” Lake City Principal Deanne Clifford said in a district news release.