Lawmakers in Russia have called a US-led coalition strike against Syrian pro-government forces an "act of aggression". This comes after 100 fighters aligned with Syrian President Bashar al-Assad were killed in the attacks, which came late on Wednesday and early on Thursday. The heavy death toll underscored the large size of the attacks, which included about 500 opposing forces, backed by artillery, tanks, rocket launchers and mortars. No American troops were killed or wounded.