At least eight people have been injured Tuesday after an explosion in the Gulf of Mexico off the Louisiana coast, according to reporter Chris Welty.

Four people were transported to the hospital and four refused treatment after the natural gas well explosion at Belle Isle Field in St. Mary Parish, Louisiana, news outlets reported.

Texas Petroleum Investment Company said contractors working to cap a well were injured when a spark ignited natural gas, KATC3 reported. The incident began Sunday while workers were trying to plug the abandoned well, the company said.

Crews “were attempting to plug a well, and it got away from them” Sunday, the Louisiana Department of Natural Resources told KATC3.

The crews called in Wild Well Control to help, and “something” happened Tuesday that ignited the gas, KATC3 reported.

“The workers are receiving medical treatment and crews are on the scene to protect the environment and bring the well under control,” the company told the TV station.

Acadian Ambulance responded with four helicopters and five ground units, a spokesperson told KATC3. Two patients were transported by air and two by boat to Morgan City, according to the TV station.