MAIDUGURI, Nigeria - Suspected Islamist militants opened fire in a remote town in northeast Nigeria, killing at least 15 people, witnesses and a security source said.The attack on Monday night targeted Kautikari, near the Cameroon border, just 10 kilometres (6 miles) from the village of Chibok, where more than 200 schoolgirls were abducted in April. They remain captives."The were about twenty, well-armed. They came in four-wheel drive vehicles and some motorcycles. Initially, I thought they were soldiers," survivor Jonah Umaru said by telephone."The man running behind me was gunned down as I was fleeing. Afterwards, there were 15 people lying dead in the streets."Suspected Boko Haram gunmen kidnapped 172 women and children and killed 35 other people this month near the same area.Violence by Boko Haram, which is fighting to establish an Islamic state in Nigeria, has killed 10,340 people so far this year, according to a count by the Council on Foreign Relations last month.