they're infiltraters. they talked amongst themselves and then one said, fire, and they shot all three of them in the chest. then they dragged them by their feet and threw them into a well. >> we went to the place he described. there are reports that as many as 20 or 30 suspected infiltraters may have been executed by malian forces here. >> you can see lines of blood going all the way down. and some of this earth has clearly been pushed down to hide the bodies at the bottom. the malian government said it will investigate what happened. but it's clear several wells hold awful secrets. >> there's a horschel smell coming from down this well and you can see the blood spattered all around. there's no doubt the people were killed here. and there's that's just a few hundred yards from a crowded bus station just over there. at the bus station everyone's heard of the killings but it's hard to find anyone who will admit to having seen it. people are afraid of the consensuses of speaking out. -- sequences of speaking