ISTANBUL (AP) — Police in Istanbul conducted a series raids in the city targeting Islamic State suspects, the state-run news agency reported Thursday, following the gunfire and suicide bomb attack at Ataturk Airport which killed 42 people.

Anadolu Agency said police searched several addresses in Istanbul's Pendik, Basaksehir and Sultanbeyli neighborhoods but it was not clear if any arrests were made. There was no word on whether the raids were directly linked to the attack.

Authorities blamed the IS group for the coordinated attack by three assailants late Tuesday on one of the world's busiest airports, that also injured more than 230.

There was no immediate claim of responsibility by the militant group.

Seperately, security forces killed two suspected Islamic State militants at the border with Syria, Anadolu and other news reports said Thursday.

Anadolu, citing unnamed security sources, says the two Syrian nationals were killed on June 25 while trying to cross the border illegally and ignored security forces warnings to stop.

One of the two militants was wanted by Turkey on suspicion that he would carry out suicide attacks in the capital Ankara or in the southern city of Adana, Anadolu said.

Turkey shares long, porous borders with both Syria and Iraq, where IS controls large pockets of territory, and the government has blamed IS for several major bombings over the past year, including in the capital Ankara, and on tourists in Istanbul.