MILWAUKEE (WSAU) Police say homemade explosive devices were places around Riverside High School in Milwaukee. One of them detonated, but didn’t cause any substantial damage.

The school was put under lockdown, and two students were arrested. Both are facing felony charges.

A school spokesperson says the explosives were bottles with chemicals inside. At least one started foaming. Students were sent home at regular dismissal time, and school is scheduled to resume this morning.