WEBSTER GROVES, Mo. — A threat posted to social media has put Webster Groves High School on lockout. This means that no one can enter or leave the building but classes will proceed as scheduled.

The school district says that the lockout is to keep the school safe for students and staff. The school and police have not yet elaborated on the nature of the threat.

Threats posted to social media have caused similar security concerns at other local schools. A student accused of a threat toward Edwardsville High School is behind bars on multiple felony charges. A Marquette High School student was accused of an “AirDropped social media threat” last November. That school went virtual for days as they investigated the messages.

This is a developing story. More details will be posted here as they come into the FOX 2 newsroom. Refresh this page for the latest update.