NATO airstrikes and artillery have killed a further 92 suspected Taliban fighters, the alliance reported Monday, pushing its toll of militant dead in a 10-day offensive past 500. The latest deaths came when insurgents staged a counterattack in Kandahar province on Sunday, a NATO statement said. It added that the casualties in the province's Panjwayi and Zhari districts were in addition to 94 militants it had already reported as dying in a clash earlier that day. There has been no independent confirmation of the casualty numbers from Operation Medusa, which began Sept. 2. Hostilities have prevented journalists from reaching the battlefield. Taliban spokesmen have disputed the high figures and said the alliance should display bodies as proof. The fatalities reported Monday bring the toll so far to at least 510. NATO has said that 20 foreign soldiers have died, 14 of them in British reconnaissance plane crash. It says it has yet to confirm any of the several civilian casualties reported by Afghan government and hospital officials.