TEWKSBURY, Mass. — Tewksbury police have arrested a high school student in connection with social media posts that threatened school shootings and a suicide pact.

Authorities charged the 15-year-old girl Friday with making threats and conspiracy. Her name wasn’t released.

Police detained the girl Thursday after the threats were discovered. Tewksbury Memorial High School was temporarily locked down Thursday.

Officials say the student posted on Facebook that she wanted to get two guns and make a suicide pact. Police say a Winthrop High School student responded by asking if they could shoot up schools first, and the Tewksbury student wrote “let’s do it.”