Fighters of the Islamic State in Iraq and the Levant (ISIL) on Friday captured key towns in eastern Syria adjoining territory the al Qaeda splinter group has seized in Iraq, a monitoring organization said.

The Islamists, whose stated aim is to create a strict Islamic state straddling national borders, took over the towns of Muhassan, Albulil and Albuomar, the British-based Syrian Observatory for Human Rights said.

ISIL, which opposes Syrian President Bashar al-Assad, has also been fighting rival rebel groups in Deir al-Zor, an oil-producing eastern province of Syria devastated by the three-year-old civil war. […]