History Today: The deadly Deepwater Horizon blast that led to a massive oil spill

On April 20, 2010, the Deepwater Horizon oil rig, drilling at the Macondo Prospect in the Gulf of Mexico, exploded and later sank. It would go on to become the largest marine oil spill in history. Also, on this day in 1999, a shooting at Columbine High School in Colorado left 14 people dead, including the two teenage gunmen. It remains one of the deadliest school shootings in the United States

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