A U.S.-led coalition air strike in Syria hit an oil refinery run by the Islamic State of Iraq and al-Sham (ISIS) militants near the border with Turkey on Sunday, killing 30 people, the Syrian Observatory for Human Rights reported. Rami Abdulrahman, who runs the Observatory, said the dead were refinery workers and ISIS militants. The targeted refinery was just northeast of the town of Tel Abyad near the Turkish border, he said. Asked about the report, a spokesman for the U.S. Combined Joint Task Force overseeing the fight against ISIS, he said: "When an allegation of civilian casualties caused by U.S. or coalition forces is determined to be credible, a thorough investigation would be launched to determine the accuracy of the claim and any circumstances surrounding it." The spokesman said U.S. and coalition forces had implemented "significant mitigation measures within the targeting process and during the conduct of operations to reduce the potential of civilian casualties and collateral damage."

In November, the United Nations estimated ISIS's revenue from oil ranged $846,000 to $1.6 million a day. But the Pentagon has assessed that oil was no longer the main source of revenue for ISIS. Western diplomats have said this was due to air strikes on oil installations and a plunge in global oil prices that has affected black market prices as well.

Meanwhile, it was reported that more than 200 Iraqi Turkmen women have been abducted by ISIS militants, chairman of the Iraqi Turkmen Front Arshad Al-Salehi said. Speaking at a celebration organized by the Turkmen Women's Union to mark International Women's Day in the city of Kirkuk, northern Iraq, Al-Salehi said this is a "sad day" for Turkmen women. He claimed that many others have been raped and killed. Al-Salehi pointed out that "hundreds of pregnant Turkmen women who fled from Mosul and Tal Afar died after going into labour while on the road and that many of their infants died as well." Artist Nursal Kojho told the Anadolu Agency that women in Kirkuk were suffering because of ISIS's attacks. Nursal said: "Iraqi women, especially mothers who scarify their children for the country are living difficult days. As we fight terrorism, we lose our children, our husbands and brothers and I aimed with my paintings to illustrate that and to say stop the sound of weapons, we do not want women to cry."

The Iraqi forces along with Shiite militias fight ISIS militants to recapture Tikrit. Some 30,000 men have been involved in a week-old operation to recapture Tikrit, one of ISIS's main hubs since they overran large parts of Iraq nine months ago. And on Monday, Kurdish peshmerga forces launched an offensive south and west of the oil city of Kirkuk, further increasing the pressure on the last ISIS strongholds east of the Tigris River.