Turkey has stepped up military operations against Kurdish militia positions inside northern Iraq in recent weeks, using planes, helicopters and drones to hit targets belonging to the Kurdistan Workers’ Party in the regions of Metina, Zap and Avashin-Basyan.
The Kurdistan Workers' Party, or the PKK, has bases in northern Iraq from which it has launched attacks against Turkey in a decades-long push to gain greater autonomy for the Kurdish people.
The conflict between the Turkish army and the PKK in Iraq escalated in the 1990s, when Turkey launched a number of ground operations in northern Iraq following the 1991 Gulf War.
The latest attacks are seen as part of a long-running Turkish campaign in Iraq and Syria against the PKK and the Syrian Kurdish YPG militia, which is backed by the US.
Both organisations are regarded as terrorist groups by Ankara, although the US and EU list only the PKK as a terrorist group.
What is the PKK?
The PKK was formed in 1978 by Abdullah Ocalan, a radical Marxist who found support from the Syrian government under Hafez Al Assad.
The group took up arms in 1984, waging an insurgency against Turkey from its bases in the south-eastern part of the country as well as from northern Iraq.
For the PKK, the purpose of the conflict against Ankara has been to gain greater cultural and political rights for the Kurdish people, initially with the objective of establishing an independent state. In later years, however, demands have shifted to focus on greater Kurdish autonomy within Turkey.
There are approximately 30 million Kurds living in the Middle East, primarily in Iran, Iraq, Syria and Turkey. They make up nearly one fifth of Turkey’s population of 79 million.
The PKK has long used the rugged terrain of northern Iraq as a rear base from which to stage attacks against Turkey.
The Kurdish region had gained autonomy from Iraq following the Gulf War in 1991 and the US-led coalition's imposition of a no-fly zone over the country, which protected Kurdish militias from attacks from Saddam Hussein's regime but did not stop the rivalry between the various rival factions.
Since the war, relations between Ankara and the Kurdish Democratic Party — the dominant Kurdish party in Erbil, Iraq — have improved, largely due to growing trade.
Over the past several decades, Turkey has conducted cross-border aerial and ground operations against the PKK, has sent in commandos to support its offensive and has set up military positions inside Iraq.
More than 40,000 people have been killed in the conflict so far.
The Iraqi response to Turkish operations
Turkish officials privately say they believe Baghdad is firmly on their side in their fight against the PKK.
But the Iraqi government has expressed frustration with Ankara over recent increased attacks, especially as it has come under intense internal pressure to expel Turkish forces.
Publicly, Iraq has repeatedly said the presence of Turkish troops in the country is a “blatant breach of the UN charter” and is unauthorised by the government.
Last week, the Iraqi government delivered a “strongly worded” protest note to the Turkish ambassador, the foreign ministry said in a statement, and called on Turkey to withdraw all of its forces from its territory.
Populist Iraqi cleric Moqtada Al Sadr also warned Ankara about its operations in the country last week, saying Iraq “will not be silent” if Turkey continues to breach its sovereignty by bombing areas in northern Duhok province, which is part of the semi-autonomous Kurdish region.
Adopting a harder line, some Iran-backed Iraqi militias have been accused of firing rockets at Turkish positions inside Iraq.
But the Iraqi government has yet to take any direct action to stop Turkey from conducting attacks within its borders.
In response to Baghdad summoning the Turkish ambassador, Ankara handed a diplomatic note to the Iraqi envoy on Thursday accusing the Iraqi government of making “unfounded allegations” about Turkey's military operation.
Turkey's justification for attacks on PKK targets in Iraq
Ankara has for years justified conducting operations inside Iraq by claiming Baghdad is unable to prevent the PKK from carrying out attacks against Turkey, said Sajad Jiyad, an analyst with the Century Foundation.
“The idea is that Turkey is engaging in a form of self-defence, that Iraq cannot stop the PKK from being active in Iraq which will lead to more attacks in Turkey,” Mr Jiyad told The National.
“They believe they have an agreement signed with the previous regime of Saddam Hussein that allows them to conduct cross-border military activities.”
A Kurdish official told The National that the “Turkish operation is being carried out by Turkey in cooperation with the Iraqi federal government; they have a strategic agreement on that".
The official did not elaborate further or give any more details.
Since 2017, Turkey has increased the number of its military posts and bases in Iraq, seeming to have secured the tacit agreement of the most powerful Kurdish political party, the Kurdistan Democratic Party (KDP), Mr Jiyad said.
Turkey has full approval to “move military personnel and equipment across the border from Turkey into Iraq freely and to conduct aerial surveillance and military air strikes”, he said.
“The attacks are becoming much more intense and the situation is becoming more dangerous as the Iraqis cannot do anything to stop Ankara and the PKK taking matters into their own hands.”
Iraq must show that it has control over its borders to stop these issues from becoming more complex, he said.