Multiple historically Black colleges and universities in the South were on lockdown or cancelled classes on Thursday over potential threats.

Hampton University, Virginia State University, Bethune Cookman University and Alabama State University were on lockdown after receiving “potential threats to campus safety,” according to posts on school social media pages.

The lockdowns come one day after Charlie Kirk, a prominent conservative activist and Trump ally, died after a shooting at a Utah college campus event and on the heels of a wave of active shooter hoaxes at several other college campuses across the country.

Spelman College in Atlanta, Georgia, also issued a shelter-in-place order, which was lifted on Thursday afternoon after the college said neighboring Clark Atlanta University received a threat. Atlanta Police told CNN they are assisting.

Southern University and A&M College in Baton Rouge, Louisiana, was also on lockdown but has since lifted it, and all campus activities and classes are cancelled for Thursday, Friday and through the weekend, it told CNN.