Exclusive: The Archbishop of Jos tells Channel 4 News that the attacks on Christian villages in Nigeria, in which an estimated 500 people have been killed, were "systematic and quite well organised".
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Several hundred people are believed to have been killed in the attacks on three predominantly Christian villages in Jos, Plateau State, which took place on Sunday.
The Archbishop of Jos, Rev Benjamin Kwashi, told Channel 4 News: "I first of all began to get a report as I was heading on to the church that one of the villages had received visitors who are said to be Muslim attackers. They were killing anybody, anybody.
"Even children were all massacred. One day old. A woman was delivering and even she with the undelivered baby were all killed. Everybody - women, children, men and all.
"A little later in the day I got information that corpses were littered by the other village, and later on in the day again, more corpses were discovered from the third village.
"When I started asking I was told that there were bus loads of Muslim Fulani men who came armed with swords and machetes. The attack was quite systematic and quite well organised. It didn't leave the villagers with any chance to escape at all.
"For any group to beat the curfew hands down must be an organised group. I mean, it is a military curfew together with the police, so for any group to do that they must be really, really, really, very organised.
"Secondly, if you look at the mercilessness of the murder and the mass massacre, it can't just be done like that. The people there were left with no chance at all. Children were killed, old people were killed, young people were killed. Many of them were shot at then cut.
"But also if you look at the cuts, you will see that they are sharp knives and most of the cuts are at the back and neck. And quite a number of heads were severed from the body. So, they are really fighters in my opinion.
"And the way - in two hours, three villages. It must be people who knew what to do and were trained in how to do it.
"If we had an idea of who it was, the problem would be solved. That's what we have been facing in Jos, we don't know who.
"These are faceless people. If they could identify themselves we could ask them 'what do you really want' and some meaningful negotiations can be done, and with some skill, I believe, blood should not be shed. Blood should never be shed of any human being."