NIAMEY, Aug 22 (Reuters) - Tuareg-led rebels in Niger said late on Tuesday they had killed 15 government soldiers in a clash at Gougaram in the West African country's remote Saharan north, where uranium is mined. "There was a clash between us and them, and 15 of them were killed and two vehicles destroyed," the rebel Niger Movement for Justice (MNJ) said on its blog http://m-n-j.blogspot.com/. Government officials in the capital Niamey could not confirm the fighting.