Threat prompts lockdown at Green Tree Preparatory

MILWAUKEE (CBS 58) -- A Milwaukee public school is put on lockdown just days into the school year. 

The Milwaukee Public School District says around 8:30 Friday morning, just before the start of the school day, a threat was made to a member of the staff at Green Tree Preparatory to cause harm to students and staff members. 

Teachers and staff moved students inside the school to a secure location and students on buses en route to Green Tree Preparatory were re-routed to Clara Barton Elementary. 

A spokesperson for MPS says he's proud of how their staff sprung into action to keep everyone safe. 

"We have an incredible staff here at Green Tree, incredible safety as well. they were able to react extremely quickly in order to keep these students safe so we're just left feeling so grateful for the staff here. and the students did such a good job, obviously, this is not how you want a school day to start but they did great," says Andy Nelson, Director of Communications for Milwaukee Public Schools. 

MPS says all students have been brought to Green Tree and classes have resumed as normal. No students or staff were injured. 

Milwaukee Police say they are investigating.