Nigerian student allegedly killed by cultists

According to James Roberts who shared the sad news on Facebook, a young man called Kelly Ngo  Sylva was allegedly brutally cut down in his prime by a cult group last night.
I really don't understand the circumstances behind his death because of the various codes being used but his friends have been mourning him online. I hate to imagine what his family is going through right now.

Kelly is being described as a very gentle and reserved person, so what happened?