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 that it has opened its bases to the U.S.-led air campaign against IS , boosted security along its 900-kilometre (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 are also 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-Turkish 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 that 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 say 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.

Clashes between Turkey's security forces and the rebels of the Kurdistan Workers' Party, or PKK, reignited in July, shattering a fragile peace process.

Turkey has carried out numerous airstrikes against PKK positions in northern Iraq and imposed extended curfews in flashpoint neighbourhoods and towns in its mainly Kurdish southeast as security forces battle Kurdish militants linked to the PKK.

The conflict between government forces and the PKK, considered a terrorist organization by Turkey and its Western allies, has killed tens of thousands of people since 1984.

As a result, "Turkey continues to identify the main problem as the PKK and (Syrian President Bashar) Assad," said Svante Cornell, director of the Central Asia-Caucasus Institute. "Turkey continues to view (IS) as a lesser evil."

Sinan Ulgen, a visiting scholar at Brussels-based Carnegie Europe, agreed Turkey was slow to react to the threat posed by IS, showing to much leniency toward the jihadist recruits who used its territory to enter Syria, in the hope that they would help bring Assad down.

However, "it's not the same battle, the strategies are different," Ulgen said. "What's going on in the southeast against the PKK is a low-intensity conflict which is highly visible. Turkey's battle against the Islamic State is less visible and is going on behind the scenes."

He said the crisis with Russia, triggered by Turkey's downing of a Russian warplane it said violated its airspace, has prevented Turkey from carrying out airstrikes against the Islamic extremists. Moscow has warned Turkey against violating Syrian airspace and suggested it would respond to any threat to its aircraft.

"The U.S. and Turkey were in the middle of a preparing a joint campaign," Ulgen said. "If the crisis hadn't occurred the fight (against IS) would have been more visible."

The Kurdish rebel attack late Wednesday targeted a police station and adjoining housing for officers and their families in the town of Cinar in mostly Kurdish Diyarbakir province.

The force of the blast caused a house near the police station to collapse. The dead included the wife of a policeman and a 5-month-old baby who were killed in the police lodging and two children who died in the collapsed house, the private Dogan news agency said.

"We were sleeping and woke up thinking it was an earthquake," Shafee Dagli, a Cinar resident told The Associated Press. "Then the clashes started. They lasted for about 2 1/2 hours, from 11.30 p.m. to 2 a.m."

"We were so frightened. We were awake watching TV when all these fragments blew into our yard from the blast," said Hediye 0zaltay, a mother of five who lives behind the police station. "At first we thought there was an earthquake. Then I looked at the police station and saw fire."

Associated Press Writer Dominique Soguel contributed from Cinar, Turkey.