Five people have been rushed to hospital following an explosion and fire at an industrial site in Sarnia, Ont., Saturday afternoon.

Sarnia Mayor Mike Bradley said one person was critically injured in the explosion at Veolia ES Canada Industrial Services plant.

Emergency services responded to reports of a blast at the remote industrial site on Scott Road at approximately 2:40 p.m.

Three others suffered serious injuries and one has minor injuries, Bradley said.

According to police, all those injured were taken to a local hospital. One of them, a man in his 30s with severe burns, was subsequently airlifted to a hospital in London, Ont., a spokesperson with Ornge air ambulance services told The Canadian Press.

The subsequent fire at the facility, which is located in a remote industrial area, has been extinguished, Bradley said.

Local Lambton County paramedics said the incident was “isolated to the site.”

It was not immediately clear what caused the explosion, but police said investigators from the ministry of labour were on scene.

According to its website, Veolia provides industrial cleaning and maintenance services.

Sarnia is located in southwestern Ontario, approximately 290 kilometres from Toronto.

With files from The Canadian Press