In an escalating campaign Ankara aimed at rooting out terror, Turkey's military carried out a new wave of air and artillery strikes against Islamic State (IS) jihadists in Syria and Kurdish militants in northern Iraq.
The two-pronged operation against IS and the outlawed Kurdistan Workers Party (PKK) -- two groups who are themselves bitterly opposed -- came after a week of deadly violence in Turkey the authorities blamed on both organisations.
The PKK blasted the air raids on its northern Iraq mountain stronghold, saying a fragile ceasefire that had been in place since 2013 with Ankara "no longer has any meaning".
After raids overnight, Prime Minister Ahmet Davutoglu said Turkish war planes were carrying out new daytime raids against IS in Syria and PKK in northern Iraq.
Meanwhile Turkish ground forces were pounding targets belonging to both groups with artillery, he added.
"No one should doubt our determination," he added. "We will not allow Turkey to be turned into a lawless country."
The raids against IS, which had begun before dawn Friday, marked a major shift in policy towards the group by key NATO member Turkey, which has faced severe criticism from its Western allies for not doing enough to combat the jihadists.
But the "anti-terror" operation has now been expanded to strikes on the PKK in neighbouring Iraq, where the banned group's military forces are based.
Davutoglu's office said shelters and warehouses containing PKK weapons were hit in the northern Iraq operation, listing seven locations where the strikes had been carried out including Mount Kandil, where the PKK's military leadership is based.
Davutoglu said he had earlier Saturday spoken to Massud Barzani, the president of the Kurdish-ruled autonomous region in northern Iraq, who expressed his "solidarity" with the operation.
PKK ceasefire over?
The air strike raised questions about the future of the fragile peace process between Turkey and the PKK, which has for decades waged a deadly insurgency in the southeast for self-rule that has claimed tens of thousands of lives.
The PKK's military wing, the People's Defence Forces (HPG), said in a statement on its website that Turkey had "unilaterally terminated" the ceasefire.
"Amid this intense aerial bombardment, the truce no longer has any meaning," it said.
The violence in Turkey erupted after the killing of 32 people in a suicide bombing Monday in the Turkish town of Suruc on the Syrian border carried out by a 20-year old Turkish man linked to IS.
That attack sparked an upsurge in violence in Turkey's Kurdish-dominated southeast, where many accuse Turkish authorities of collaborating with IS.
The PKK then outraged the government by claiming the shooting dead of two Turkish police at home while they slept.
Turkish security forces Saturday launched new raids to arrest suspected IS and PKK members in Istanbul and other cities, adding to hundreds of detentions already made the day earlier.
A total of 590 people have so far been arrested across Turkey over links to terror groups and for allegedly posing a threat to the state, Davutoglu said.
As well as IS and the PKK, the arrest operations also targeted suspected members of the PKK's youth wing, The Patriotic Revolutionary Youth Movement (YDG-H), and the Marxist Revolutionary People's Liberation Party Front (DHKP-C).
With tensions running high across the country, Turkish police late Friday used tear gas and rubber bullets to disperse a protest in the Istanbul district of Kadikoy by hundreds of people to denounce IS violence.
Protesters in the anti-establishment district of Gazi also defiantly carried the coffin of Gunay Ozarslan, a female activist killed in clashes with police on Friday during a raid on leftist militants, an AFP photographer said.
The Istanbul authorities banned a planned anti-jihadist "peace march" scheduled to take place in the Turkish metropolis on Sunday, citing security and traffic congestion. Its pro-Kurdish organisers said the event had now been cancelled.
'Deal on air base'
Turkey has been accused of colluding with IS extremists in the hope they might further Ankara's aim of toppling Syrian President Bashar al-Assad.
Ankara has always vehemently denied the claims but the NATO member has dodged playing a full role in the US-led coalition assisting Kurds fighting IS militants.
Now, however, Ankara has finally given the green light to US forces for the use of its Incirlik base for air strikes against IS in Syria and Iraq, according to American and Turkish officials.
Foreign Minister Mevlut Cavusoglu said a "framework" accord had been agreed with the United States on the issue, which also foresees the creation of "safe zones" free of IS jihadists in Syria.
He said such zones would give a chance to Syrian refugees -- 1.8 million of whom are in Turkey -- to "return to their homeland".