An oil rig has exploded in the Gulf of Mexico near Grand Isle, Louisiana, sending four people to the hospital, with two believed to be missing, according to the United States Coast Guard.

According to Jefferson Parish Councilman Chris Roberts, the oil rig is a shallow water production platform owned by Black Elk Energy that sits near West Cote Blanche Bay.

Early reports indicate that two helicopters, an airplane and some small boats have been sent into the area. Although, it is not yet known if the fire caused by the explosion has been extinguished.

There are no reports of an oil spill as the result of this accident. Officials from the Louisiana governor’s office say the explosion happened while the crew was performing maintenance.

Black Elk Energy, which is an independent oil and gas company from Houston, Texas, was not available for comment.