Eleven workers are missing and another seventeen have been wounded after an explosion at an oil drilling platform off the Louisiana coast. Over 100 people were aboard the Deepwater Horizon when the blast occurred Tuesday night. Firefighters were still fighting the blaze as of early Thursday morning. Four of the wounded are in critical condition. On Wednesday, Mary Landry of the US Coast Guard said rescue boats are searching for the eleven missing workers.

Mary Landry: “We have no idea where the eleven people, the unaccounted-for personnel, are at this time, and we’re going to continue to search.”

The rig was under contract to the oil giant BP, which has come under scrutiny for major safety flaws in its US operations. Fifteen people were killed and hundreds were injured in an explosion at a BP refinery in Texas in 2005. The company was fined $87 million last year for failing to make safety improvements at the refinery under a settlement with government regulators. Just last month, BP was fined $3 million for safety flaws at a refinery in Ohio. BP has also been fined for a 2006 pipeline spill in Alaska.