In Mauritania, the government has alerted some troops for possible operations on the frontier with Mali, after reports of clashes in northern Mali between Touareg tribesmen and local villagers. There are already some 35,000 Touareg refugees from Mali living in Mauritania, and Mauritania would prefer not to have any more. As an added incentive, the defeated Algerian Salafist movement, a violent Islamist sect, has had some influence among the Touareg. As a result, several countries in the region, including Mauritania and Mali, have concluded "hot pursuit" agreements. This became more than just a suspicion last month, as police went looking for three Algerian Islamic terrorists who escaped from jail in April 27th. The pursuit uncovered many other supporters of Islamic radicalism, and led to dozens of additional arrests over the past few weeks. Apparently, several major terror attacks were planned, including kidnapping foreigners and attacks on security forces. Mauritania had long resisted the idea that Islamic radicals were plentiful in the country. But the last few weeks has revealed a far different picture. Some of the men interrogated indicated long participation in Islamic terrorism, in one case back to the 1998 bombings of U.S. embassies in East Africa. American Special Forces have been in Mauritania, and the surrounding Sahel region, for several years, based on intelligence indicating this was an area al Qaeda would try to use for refuge. That is turning out to be the case.