ANKARA, Turkey --Turkish tanks and artillery attacked the Islamic State group in Iraq and Syria in retaliation for the suicide bombing in Istanbul that killed 10 tourists, Turkey's prime minister said Thursday -- the country's first significant strike against the Islamic extremists in months.

Turkey agreed last year to take on a larger role in the fight against IS amid two major attacks that left 135 people dead.

But critics contend the country has shown only limited engagement, striking only when attacked and focusing instead on quelling Kurdish rebels.

Turkey rejects the accusations, pointing out it has opened its bases to the U.S.-led air campaign against IS, boosted security along its 550-mile border with Syria to try to prevent IS fighters from crossing it and cracked down on suspected terror cells in Turkey, detaining or deporting thousands of militants.

Turkish forces also are training Iraqi Kurdish forces fighting the militants.

Prime Minister Ahmet Davutoglu said some 200 extremists had been killed over the past 48 hours in Turkey's offensive against IS along the Syria-Turkey border and near a Turkish camp in northern Iraq.

He did not rule out possible airstrikes against the group, although a day earlier he said Russia was obstructing Turkey's ability to conduct airstrikes against IS in Syria.

The Turkish leader said Ankara acted after determining IS was responsible for the "heinous" suicide bombing Tuesday in Istanbul's main tourist district, just steps away from the landmark Blue Mosque. All of the dead were German tourists.

Turkish officials said the bomber, a Syrian born in 1988, was affiliated with the Islamic State group and entered Turkey by posing as a refugee.

Interior Minister Efkan Ala said seven people had been detained in connection with the bombing.

"Turkey will continue to punish with even greater force any threat that is directed against Turkey or its guests," Davutoglu said. "We will press ahead with our determined struggle until the Daesh terrorist organization leaves Turkey's borders ... and until it loses its ability to continue with its acts that soil our sacred religion, Islam."

Davutoglu was speaking in Ankara hours after Kurdish rebels detonated a car bomb at a police station in southeastern Turkey, then attacked it with rocket launchers and firearms. Six people were killed, including three children, authorities said.