(Reuters) Bozorgmehr Sharafedin - Iran's Fars news agency reported on Saturday that 13 Iranian military advisors had been killed and 21 wounded in a battle with Islamist militants near the Syrian city of Aleppo. The British-based Syrian Observatory for Human Rights confirmed the death of 20 Iranians, including 13 advisors. It said that 6 Hizbullah fighters and 15 Afghan Shi'ite fighters were also killed.