Updated

At least 1,075 people have been killed so far in Iraq in June as Sunni militants capture towns and cities in their march toward Baghdad, the United Nations says.

According to the U.N. human rights team in Iraq, there were at least 757 civilians killed and 599 injured in Nineveh, Diyala and Salah al-Din provinces from June 5-22, as troops led by Shiite-led government in Baghdad failed to stop the advance of the Islamic State of Iraq and Syria, also known as ISIS.

"This figure — which should be viewed very much as a minimum — includes a number of verified summary executions and extra-judicial killings of civilians, police, and soldiers who were hors (de) combat," said U.N. human rights office spokesman Rupert Colville, using the French term for soldiers who have signaled they are no longer combatants.

The Iraq team said another 318 people were killed and 590 injured during the same time in Baghdad and areas in the south, many of them from least six separate vehicle-borne bombs. It also is trying to verify what Colville called "a number of alleged human rights violations that have been taking place in Iraq" since ISIS's advances in early June.

Colville told reporters in Geneva that kidnappings of foreigners and others continue in the northern provinces and in Baghdad, including 48 Turkish citizens taken from Turkey's consulate when ISIS captured Mosul and 40 Indian nationals who had been working for an Iraqi construction company.

But he said 16 Georgians reported kidnapped 10 days ago have been released, and 44 other foreign workers abducted by ISIS when they captured Al-Door also have been freed and returned safely after local tribal leaders negotiated between the Iraqi army and ISIS.

"Tragically some of those who have been abducted have been subsequently found dead, and summary executions also apparently continue to take place," Colville said.

The figures came after Shiite Turkmen villagers in northern Iraq claimed that ISIS carried out a "savage massacre" in four villages near the city of Kirkuk.

The Associated Press contributed to this report.