Iraqi government forces made significant advances on Wednesday in an effort to break an Islamic State siege of the country’s biggest refinery just outside the city of Baiji, an army commander and state television said.

Backed by Shi’ite militias, government forces have seized 60 percent of the city centre and are close to opening a corridor to Islamic State militants ringing the refinery, 200 km (130 miles) north of the capital, said the commander.

A deserted area between the edge of the city and the refinery may be difficult to cross because of roadside bombs and snipers, security officials say. […]