BAGHDAD (Reuters) - Iraqi warplanes have struck Islamic State targets inside Syria in retaliation for recent bomb attacks in Baghdad by the group, Prime Minister Haider al-Abadi said on Friday.

Iraq's Prime Minister Haider al-Abadi announces the start of an offensive to retake the western side of Mosul as troops begin to move towards Islamic State, in this still image from video by Iraqiya TV February 19, 2017. Iraqiya TV/via Reuters TV

It appeared to be the first time Iraqi jets have conducted such raids across the border. A Syrian source said the strikes had been coordinated with Damascus.

Islamic State, which is now on the defensive after losing control of eastern Mosul in Iraq to a U.S.-backed Iraqi military offensive, has claimed responsibility for several car bombs in Baghdad in the capital in the past few weeks.

“We are determined to chase terrorism that tries to kill our sons and citizens, wherever it is found, so we gave orders to the air force command to strike Islamic State positions in (the Iraqi town of) Hosaiba and Albu Kamal inside Syrian territory as they were responsible for recent bombings in Baghdad,” Abadi said in a statement.

“The heroes of the sky executed the operation and responded to the terrorists with amazing success.”

A military statement said the strikes had taken place on Friday morning using F16 fighter jets and had destroyed Islamic State headquarters in Albu Kamal.

“The strikes targeted Islamic State’s headquarters used for making car bombs in Albu Kamal... after Iraqi intelligence received tips from their sources inside Syria,” a senior security official told Reuters.

A source close to Syria’s foreign ministry said the operation had been carried out in “complete coordination” with the Damascus government.

The United States said it had also helped the Iraqis by providing intelligence.

“Yes we were aware, yes we supported it as well with information,” Pentagon spokesman Captain Jeff Davis told reporters. “It is a good strike, it is a valid strike, it was a strike against ISIS targets,” he said, using an acronym for Islamic State.

The jihadist group has separately come under attack in Syria by warplanes from Russia, Turkey and a U.S.-led coalition, all of which are supporting different offensives against it in the country.