Islamic State insurgents have seized several towns and villages from rival Islamist groups in the Syrian province of Aleppo, opening the way for further westward advances, an organization monitoring the war in Syria said on Wednesday.

Already in control of large areas of northern and eastern Syria, Islamic State’s latest gains include the towns of Turkmen Bareh and Akhtarin, 50 km (30 miles) northeast of Aleppo, the Syrian Observatory for Human Rights, which is based in Britain, reported.

It said at least 40 fighters were killed during the fighting. […]