Two children die from IS chemical attack in Iraq

"We recorded the death this evening of a 10-year-old girl," said Hussein Abbas, the mayor of Taza, on Friday night.

The town, south of Kirkuk, was targeted by rockets armed with suspected mustard agent.

A six-month-old baby died on Thursday of complications resulting from the attack, he said, while a three-year-old girl had died shortly after the March 9 violence.

Sources at the Kirkuk health directorate and a rights group also confirmed the deaths.

Abbas said the number of people treated after complaining of burns, rashes and respiratory problems has risen to 1,500.

A total of 25,000 people have left their homes in and around Taza, fearing another attack from the neighbouring village of Bashir, still controlled by IS, he said.

Officials have alleged that IS used mustard agent in the attack.

The samples are still being analysed, and definitive results from the Organisation for the Prohibition of Chemical Weapons based in The Hague can take several months.

While the chemical agents allegedly used by IS so far have been among their least effective weapons, the psychological impact on civilians is considerable.

Iraqi Prime Minister Haider al-Abadi has vowed the attack would not go unpunished and several air raids have already been carried out on Bashir in recent days.

Tension between the Kurdish Peshmerga who control Kirkuk and the Shia militia groups also present in the area has delayed a coordinated military operation to oust IS from Bashir.