A chemical scare prompted the closure of the emergency department at St. Joseph’s Hospital in Hamilton on Thursday night.

Someone spotted chemicals in open buckets in a car parked in front of the hospital on Charlton Ave.

The ER was closed and ambulances were rerouted as a hazardous materials team investigated.

The chemicals turned out to be a mixture of chlorine and bubble bath soap.

Everything re-opened around 10:30 p.m. after being closed for about an hour.

Hamilton Police are investigating.