Updated

Insurgents unleashed a series of attacks mostly targeting civilian areas in and around the Iraqi capital on Thursday, killing at least 16, as Islamic State militants in the country's north set oil wells ablaze in an attempt to slow government forces battling to reclaim territory.

Thirteen civilians were killed in separate attacks on an outdoor market in the Baghdad suburb of Nahrawan, a commercial street in the southern district of Abu Dashir, a residential area in the southern district of Dora and a market in Mahmoudiyah, 20 miles south of Baghdad, police officers said. At least 39 people were wounded.

In another attack, a bomb targeted a military patrol in a northeastern district, killing three soldiers and wounding seven.

Medical officials confirmed the casualty figures. All officials spoke on condition of anonymity as they were not authorized to talk to reporters.

The attacks come as government forces, Iranian-backed Shiite militias and Sunni volunteers continued their fight to recapture key areas around Saddam Hussein's hometown, Tikrit, which fell to Islamic State militants in June.

On Thursday, militants set fire to some oil wells outside the city, an oil official said on condition of anonymity as he was not authorized to release information. The smoky fires were apparently meant to obscure targets from government bombing raids, part of a wide-scale operation that began Monday.

Ajeel oil field, about 22 miles northeast of Tikrit, was one of at least four fields seized by the militants, who have used smuggled oil to finance their operations.

Gen. Abdul-Wahab al-Saadi, in charge of recapturing Tikrit and surrounding areas, told state TV the burning oil wells "will not affect us." He said operations were continuing as planned, without elaborating.

Tikrit is strategically important as a major supply link for any future operation to reclaim Mosul, Iraq's second-largest city and the extremists' biggest stronghold.