The Safari (2003)

In exchange for a big sum of money, four Thai guys went to Africa to investigate a region where mysterious murders are occurring. Armed with carbines and just enough courage, they try to put some light on these inexplicable events. However, things get more complicated than expected when their travel bus has some mechanical problems, giving them no other choice but to go all the way by foot and that decision is a bad one as they meet up with cannibals.