KIRKUL, Iraq (AFP) - Two more children have died of wounds sustained in a suspected jihadist chemical attack last week in Iraq, a local official said on Friday (March 18), raising the death toll to three.

"We recorded the death this evening of a 10-year-old girl," said Hussein Abbas, the mayor of Taza, a town south of Kirkuk that was targeted by rockets armed with suspected mustard agent.

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

Sources at the Kirkuk health directorate and a local 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 had left their homes in and around Taza, fearing another attack from the neighbouring village of Bashir, still controlled by the Islamic State of Iraq and Syria (ISIS) jihadist group, he said.

Local officials have charged that ISIS 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 ISIS so far have been among their least effective weapons, the psychological impact on civilians is considerable.

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 Shiite militia groups also present in the area has delayed a coordinated military operation to oust ISIS from Bashir.