A Boeing 737-8FB flying from Dakar to Cotonou collided with an air ambulance operated by Senegalair.
The 737, which was Ceiba Intercontinental Airlines Flight 71, diverted to Malabo and landed safely; The air ambulance did not.
The collision occurred over eastern Senegal.
The Air Ambulance presumably ran out of fuel and crashed in the Atlantic Ocean. The 737 received little damage. The Boeing 737-8FB #3C-LLY that had been in service since February 2014.
The Hawker HS-125 erroneously was flying at a level 1000 ft above their original clearance. ATC cleared the flight to 34.000 ft. (FL 340) but instead the pilots levelled of at 35.000 ft (FL 350) putting themselves on the same altitude as the opposite flying 737.
Air Traffic Control did not remind the pilots to correct their level nor did the pilots do any altitude changes before the collision took place.
2015-09-05 Ceiba 737-800 mid-air collision with HS-125 Jet over Senegal