A chemical explosion and leak Tuesday night at MC Tank Transport in Toledo, Ohio was caused by an error at a tank terminal while the material was transferred, according to reporting from CNN. Emergency response is ongoing. 

Authorities were first made available of the incident at 9:30 PM on Tuesday. 

Glycidyl methacrylate, a flammable chemical which is used in plastics, paints and coatings, was released from a 5,500 gallon tank. The Toledo Environmental Services was aware of the incident and reported it around 11:40 p.m. Eastern on Tuesday, according to Bryant Somerville, a spokesperson for the Ohio Environmental Protection Agency, via CNN. 

On Wednesday, the Toledo first department evacuated the area within a mile of the tank terminal. Residents within a three-mile radius were advised to shelter in place, keep doors and windows shut, and shut off AC units.

The hazardous chemical continued to release from the tank throughout Wednesday afternoon. By 4:30 p.m., Toledo Mayor Wade Kapszukiewicz said the possibility of an explosion from the tank was unlikely. 

As of 1 p.m., about 30 people were treated in the ProMedica healthcare system, which serves the Toledo area, for symptoms that were “potentially related” to the chemical leak. Two public school districts were closed. 

A sheriff’s deputy who responded to the explosion was injured on Tuesday night. 

MC Tank Transport specializes in liquid bulk transport. 

“We are working closely with Toledo Fire & Rescue and other emergency authorities, who are directing the response,” the company wrote in a statement on Wednesday. 

“We understand the serious disruption this incident has caused to nearby residents and businesses, particularly those required to evacuate their homes,” the statement continued. “We are committed to assisting those affected.”