Seven suspected Islamic State jihadists and two Turkish policemen were killed in a gun battle in the Kurdish-majority Diyarbakir city in Turkey on Monday.
The shootout was the first on Turkish soil between security forces and the militants since Ankara launched air strikes on IS targets in Syria in July.
Police have been hunting down IS suspects following the suicide bombings that killed 102 people in Ankara on October 10.
They are also tracking a four-member IS cell feared to be plotting large-scale attacks as the country gears up for Sunday’s vote with security the paramount concern.
An anti-terrorist squad launched dawn raids on several houses in a district of Diyarbakir where militants were thought to be hiding out.
The suspects opened fire and set off booby traps planted around the houses, killing two police officers and injuring five, according to the Diyarbakir governor’s office.
It said in a statement that seven IS militants had been killed and 12 arrested.
“This was an important operation... we can say we have neutralised a major Daesh cell,” deputy prime minister Numan Kurtulmus told reporters, using an Arabic name for the IS group.
“We are trying to determine any links with cells in other cities,” he added.
Number one suspect
The fighting lasted for at least two hours, an AFP journalist at the scene said, with police fearing other jihadists could be holed up in the area.
The authorities declared the IS group the number one suspect over the Ankara bombings , but many have accused President Recep Tayyip Erdogan of security failings and of turning a blind eye to the jihadists.
Erdogan himself has vowed to fight Turkey’s “enemies” as his Justice and Development Party (AKP) battles to regain the parliamentary majority it lost in June’s election, ending 13 years of single party rule.
Turkey launched air strikes on IS targets in Syria after another deadly bombing blamed on the jihadists in July before turning its fire on Kurdish rebels in northern Iraq, triggering a wave of tit-for-tat violence that ended the fragile peace process with the outlawed Kurdistan Workers’ Party (PKK).
The government says at least 160 members of the security forces have been killed in clashes or in PKK attacks, but there are no confirmed figures for Kurdish militant deaths.
Ankara, long suspected of complicity with jihadist groups fighting the regime in Damascus, later joined the coalition against IS and allowed the United States to use its territory for the air war.
A massive police hunt was also under way at the weekend for a suspected IS cell that included a German woman allegedly plotting to carry out other attacks, Turkish media reported.
The Anatolia news agency said security forces feared they were preparing a major strike “such as hijacking a plane or a vessel or detonating suicide bombs in a crowded location”.
Police have been rounding up many suspected jihadists in the past two weeks, including four accused of having a direct role in the Ankara attacks.
Photographs of fake Turkish identity cards allegedly being used by the wanted suspects were published at the weekend by local media, which said the woman was born in Kazakhstan but had a German passport.
One of the identity cards was said to belong to Omer Deniz Dundar, who had previously been identified by the media as one of the two Ankara suicide bombers -- although other reports had suggested the bomber was foreign.
The second bomber was officially identified last week as Yunus Emre Alagoz, brother of the man suspected of carrying out an attack in the mainly Kurdish town of Suruc on the Syrian border in July, which left 34 people dead.
Fears of further attacks are haunting Turkey in the run-up to the vote, and some smaller parties have cancelled major campaign rallies.