MOSCOW - Russia has evidence that this month's terrorist attack on the Moscow metro was organised by Arab mercenary Abu al-Valid who is believed to have succeeded the notorious Khattab, eliminated by special services in 2002. According to intelligence reports, Al-Valid was paid $4.5 million for the attack and has already left Chechnya for one of the Persian Gulf states. That information was reported on condition of anonymity by representatives of Russia’s special services. Security agents first suggested Abu al-Valid might be involved in the attack several days after the explosion, though no evidence substantiating those assertions had been available....