Activists say a cluster bomb attack on an Islamic State-held village in eastern Syria has killed at least 15 people, including women and children. Turkey's military says it has returned fire after a cross-border attack by Syrian Kurdish forces. A statement Wednesday said the People's Protection Units, or YPG, fired on Turkish territory overnight with anti-aircraft weapons from Syria's Afrin region. The YPG is the main component of the Syrian Democratic Forces, a U.S.-backed militia that is battling the Islamic State group in the extremists' de facto capital, Raqqa.