Istanbul: Eleven Turkish police officers were killed and 70 people injured Friday in a car bombing blamed on Kurdistan Workers` Party (PKK) rebels, as Turkey`s Army pressed an offensive against a Kurdish militia in neighbouring Syria.
The early morning blast almost completely destroyed the police headquarters in the southeastern town of Cizre, just north of the Syrian border and close to northwestern Iraq.
The explosion went off hours after the Turkish military shelled positions held by Kurdish militia inside Syria.
Ankara says the operation is aimed both at Islamic State (IS) jihadists and Kurdish fighters vehemently opposed by Turkey.
The bomb blast gutted the four-storey headquarters of the anti-riot police in Cizre, with television pictures showing a thick plume of black smoke rising into the sky.
Adjacent buildings also sustained severe damage.
Cizre has borne the brunt of renewed violence between the outlawed PKK and government forces since the collapse of a ceasefire last year.
Eleven police officers were killed, the state-run Anadolu news agency reported, quoting the local governorate.
More than 70 people were injured, four of them critically, Health Minister Recep Akdag said in televised comments.
Anadolu said the bomb went off 50 metres (yards) away from the building at a control post, blaming the attack on the PKK.
Security forces closed the main road to Cizre from the provincial capital of Sirnak to the north after the attack, Anadolu added.Turkish security forces have been hit by near daily attacks by the PKK since the two-and-a-half year ceasefire collapsed in 2015, leaving hundreds of police officers and soldiers dead.
The latest bombing came at a critical moment with hundreds of Turkish forces and dozens of tanks deployed inside Syria in what Ankara has presented as a two-pronged offensive against Kurdish militia and IS.
Turkey on Friday sent four more tanks over the border into Syria, said an AFP photographer at Karkamis on the Turkish side of the border.
Kurdish activists have accused Turkey of being more intent on preventing Kurds creating a stronghold along its border than fighting IS jihadists.
Ankara sees the Kurdish Democratic Union Party (PYD) and its People`s Protection Units (YPG) militia as terror groups acting as the Syrian branch of the PKK.
Ankara`s hostility to the YPG puts it at odds with its NATO ally, the United States, which works with the YPG on the ground in the fight against IS.
Pro-Ankara Syrian fighters, backed by Turkish tanks and fighter jets, on Wednesday seized the Syrian town of Jarabulus that had been held by IS since 2013 in a lightning raid.
On Thursday, Turkey again shelled the Kurdish militia fighters, saying they were failing to observe a deal with the US to stop advancing in jihadist-held territory.
Anadolu quoted security sources as saying that the military would continue to intervene against the PYD until it began to retreat.Meanwhile sounds of blasts were still audible from Jarabulus as pro-Ankara fighters blew up unexploded ordnance, the AFP correspondent said.
US Vice President Joe Biden, visiting Turkey on Wednesday, made clear that Washington has warned the YPG not to move west of the Euphrates after recent advances, or risk losing American support
Murat Karayilan, one of the top Iraq-based leaders of the PKK, said this week that the group was infuriated by the Turkish operation in Syria.
He claimed the campaign resulted from an "agreement" between Turkey and IS, alleging that "what is happening is an exchange rather than a military operation".
"ISIS has never abandoned a town in one day without putting up a fight," he told the pro-PKK Firat news agency.
"This dangerous agreement will extend the lifespan of ISIS."
The PKK has kept up its assaults in Turkey in the weeks since the unsuccessful July 15 coup by rogue elements in the military aimed at unseating President Recep Tayyip Erdogan.
The government for its part has vowed to press on with the campaign to eradicate the PKK from eastern Turkey after a purge in the army of those accused of carrying out the coup.
The military has conducted several operations and imposed punishing curfews in towns and cities in southeast Turkey over the past year, including Cizre, a bastion of PKK support.
Over 40,000 people have been killed since the PKK first took up arms in 1984 with the aim of carving out an independent state for Turkey`s Kurdish minority.
It is proscribed as a terrorist group by Turkey, the European Union and the United States.