BAGHDAD (Reuters) – Two car bombs in Baghdad killed at least 14 people on Thursday, police and medics said, part of a surge in violence across the capital at a time U.S.-backed forces try to drive Islamic State from the northern city of Mosul.

Islamic State claimed responsibility for the first blast which went off in Baghdad’s eastern al-Obeidi area during the morning rush, killing six and wounding 15.

The ultra-hardline Sunni group said it had targeted a gathering of Shi’ite Muslims, whom it considers apostates.

The second explosion hit the central Baghdad district of Bab al-Moadham near a security checkpoint, killing eight. There was no immediate claim of responsibility. Both bombs had been left in parked vehicles.

More than 60 people have been killed in Baghdad in attacks over the past week as Islamic State intensifies its campaign of violence in the capital as a 100,000-strong alliance of Iraqi forces extends its advances against the group in Mosul.

Mosul is Islamic State’s last major stronghold in the country. The group has lost most of the territory it seized in northern and western Iraq in 2014, and ceding Mosul would probably spell the end of its self-styled caliphate.

Lieutenant General Talib Shaghati, Iraq’s joint operations commander, told Reuters on Wednesday that pro-government troops had retaken about 70 percent of Mosul’s eastern districts since an offensive began on Oct. 17.

(Reporting by Saif Hameed; Editing by Janet Lawrence and Richard Lough)