Turkish tanks and artillery attacked ISIS 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 group in months.

Turkey agreed last year to take on a larger role in the fight against ISIS, also known as the Islamic State in Iraq and Syria, 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 ISIS, boosted security along its 900-kilometre border with Syria to try to prevent ISIS 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.

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A woman prays at the site of Tuesday's suicide bomb attack at Sultanahmet square. (Yagiz Karahan/Reuters)

Prime Minister Ahmet Davutoglu said some 200 members of ISIS had been killed over the past 48 hours in Turkey's offensive 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 ISIS in Syria.

The Turkish leader said Ankara acted after determining that ISIS 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 ISIS 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," he said, citing another name for ISIS. 

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Turkish police stand guard near a building damaged by a truck bomb attack on a police station in Cinar, in the southeastern city of Diyarbakir, Turkey on Jan. 14, 2016. (Sertac Kayar/Reuters)

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.

Turkey sees ISIS as 'lesser evil,' says analyst

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 al-] Assad," said Svante Cornell, director of the Central Asia-Caucasus Institute. "Turkey continues to view [ISIS] 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 ISIS, showing too much leniency toward the jihadist recruits who used its territory to enter Syria, in the hope that they would help bring Assad down.

Istanbul Turkey Explosion targeted German tourists Jan 12 2016

People believed to be German tourists that were targeted at an explosion in Istanbul's historic Sultanahmet district are escorted back to their hotel after a suicide bomber affiliated with the Islamic State group detonated a bomb, killing 10. (Omer Kuscu/AP)

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 ISIS. 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 ISIS] would have been more visible."

Police station bomb felt like 'earthquake'

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.

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A boy stands in front of the Obelisk of Theodosius, where Tuesday's suicide bomb attack took place in Istanbul, Turkey. The country's prime minister vowed to 'punish' the Islamic State group in retaliation. (Osman Orsal/Reuters)

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 Ozaltay, 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."