MILWAUKEE (CBS 58) -- Milwaukee Area Technical College's (MATC) downtown campus was placed on lockdown Thursday afternoon, Oct. 23, after police say suspicious "masked individuals" entered the school.  

Shortly before 2 p.m., staff and students received an alert warning them to lock all doors and windows immediately.

The school was cleared, and it was determined that the suspects left, according to police. Around 3 p.m., MATC reported the lockdown was lifted and the all-clear was given. 

Officials say there is no known threat at this time. 

Anyone with information is asked to contact MPD at 414-935-7212 or to remain anonymous, call Crime Stoppers at 414-224-TIPS.