April 28 (Reuters) - Following are security developments in Afghanistan at 0800 GMT on Saturday: KABUL - The Taliban said they had released a French woman aid worker abducted early this month, but there was no immediate confirmation from Kabul or Paris. HELMAND - U.S.-led troops killed 10 Taliban after the militants ambushed a convoy in Gershk district of the southern province of Helmand, the U.S. military said. KABUL - President Hamid Karzai marked the 15th anniversary of the defeat of communist rule with a fresh call to the Taliban to give up their insurgency. HERAT - A soldier from the U.S.-led coalition force was killed in a clash in the western province of Herat on Friday, the force said. KHOST - A NATO air strike killed 13 Taliban guerrillas after they attacked a district government headquarters in Khost province in the east, near the Pakistani border, late on Friday, the provincial governor said. URUZGAN - At least six Taliban and four policemen were killed in a clash in the southern province of Uruzgan late on Friday, police said.