The circumstances indicate a blurred border between the countries and a decision by Iraq's Shiite government to support the Shiite regime of Bashar al-Assad.

The attack occurred after the Syrians crossed into Iraq for refuge when rebels seized the al-Yaroubiyah border crossing point in Iraq's northern province of Nineveh on Saturday.

On Saturday an Al-Arabiya correspondent reported that Iraqi forces opened fire across the Syrian border for the first time, shelling opposition positions near the crossing (called Rabia in Iraq) while snipers took up positions on buildings. (There were reports of shelling on Monday as well.)