Officials confirmed an explosion and fire at an empty ethylene dichloride storage tank at the Westlake Chemical South plant shortly before 11 a.m. Wednesday.

Joe Andrepont, Westlake Chemical community and governmental relations principal, said the explosion caused six reported minor injuries. Two of the injured were taken to Oschner Christus St. Patrick Hospital and three were taken to Lake Charles Memorial. One was treated with first aid at the scene.

Because the storage tank was empty, the fire was extinguished shortly after the explosion. A large plume of smoke was visible throughout the area, with residents posting photos on social media.

A shelter-in-place was ordered for area schools and industries, but Andrepont said that has since been lifted because there were no associated environmental issues.

Andrepont said it’s too early to tell what caused the explosion, but it is being investigated. He said the Calcasieu Office of Emergency Preparedness, Louisiana State Police, and Coast Guard were notified of the incident.