A joint Afghan-NATO operation in a volatile region in the country's dangerous south has killed 40 militants, including the Taliban's leader in that region, AP quoted a government official as saying Monday. The operation in the Nad Ali and Murja districts of Helmand province began on Thursday and continued through Monday, said Dawood Ahmadi, spokesman for Helmand's governor. Ahmadi said that 40 militants have died in the operation, though he said that government officials had recovered only seven bodies, which were given to tribal elders for burial. Ahmadi said the government knows another 33 fighters were killed through intelligence sources. The figures couldn't be independently verified. Lt. Cmdr. James Gater, a spokesman for NATO's International Security Assistance Force, confirmed that a joint operation in Helmand is under way. He said he had no casualty figures he could release. Among the dead was a Mullah Salim, a Taliban leader who was the head of the militant's council in the two districts, Ahmadi said. The councils, also called shuras, are sometimes referred to as a shadow government structure that operates separately from the Afghan government. Afghan officials admit they have little control in many areas of northern Helmand, a poppy-growing region that is heavily infiltrated by Taliban fighters. Violence has spiked across Afghanistan the last two years. More than 6,000 people have died in insurgency-related violence in 2008, according to an Associated Press count of figures based on Afghan and Western officials.