(Reuters) – Adama Simila wears a knife tied to his belt by a piece of rope, his only protection against Boko Haram, the Nigerian Islamist insurgents who have repeatedly targeted his home town in remote northern Cameroon. While the threat once came from heavily armed, battle-hardened jihadists crossing from neighboring Nigeria, today Simila knows he is more likely to die at the hands of a teenage girl strapped with explosives. “We’re here to look out for suicide bombers,” said the 31-year-old, a member of a local civilian defense force in the town of Kerawa.