On the night of April 20 a surge of natural gas blasted through a concrete core recently installed by contractor Halliburton in order to seal the well for later use.11 people were killed and 17 were injured. On April 22 the rig capsized and sank. Oil began to leak out from the bottom of the rig.The cement at the bottom of the borehole did not create a seal, and oil and gas began to leak through it into the pipe leading to the surface. Since there was no gas alarm the crew had no idea about the gases rising. 4,900,000 barrels of oil had leaked into the gulf. Birds and fish get covered in a layer of oil. A ton of fish, snails, snakes, dolphins, whales, and birds have been majorly affected. As a result oil was washed up and people had to clean it up. It was hard to remove the oil because currents will move the oil around. On shore the workers removed the oil manually.