I am not an expert but I have lived in Accra on and off since the early 90's. I always thought that this was an accident waiting to happen, the South end of the runway has very little "run-off" area.
A friend of mine just posted these photos on FB:
Accra crash - 5N-BJN - Imgur
Here is a map of where the aircraft crashed, it overshot onto Giffard Road:
accra - Google Maps
From what I can tell by hearing from friends the aircraft was landing during a thunder storm and overshot the runway, apparently a Turkish Airlines crew landed shortly before the ill-fated plane and they said that conditions were very bad.