Relatives of some of the 11 men who died aboard the Deepwater Horizon oil rig are to fly over the Gulf of Mexico to mark the first anniversary of the worst offshore oil spill in US history.
On land, vigils were scheduled in Louisiana, Mississippi, Alabama and Florida to mark the moment on the night of 20 April last year when the rig, owned by Transocean Ltd, burst into flames while drilling a well for BP.
The explosion killed 11 workers on or near the drilling floor and the rest of the crew were evacuated before, two days later, the rig sank to the sea floor. The bodies of the dead were never recovered.
Over the next 85 days, 206m gallons (5m barrels) of oil – almost 20 times more than was spilled in the 1989 Exxon Valdez disaster – leaked from the well. In response, the US commandeered a fleet of vessels in an effort to contain the spill, and BP spent billions of dollars to cap the well and clean up.