ISTANBUL, Dec 11 (Reuters) - Turkey on Sunday vowed vengeance against Kurdish militants it said were likely behind twin bombings that killed 38 people and wounded 155 in what appeared to be a coordinated attack on police outside a soccer stadium in Istanbul.
The blasts on Saturday night - a car bomb outside the Vodafone Arena, home to Istanbul's Besiktas soccer team, followed by a suicide bomb attack in an adjacent park less than a minute later - shook a nation still trying to recover from a series of deadly bombings this year in cities including Istanbul and the capital Ankara.
There was no claim of responsibility, but Interior Minister Suleyman Soylu and other officials said early indications pointed to the outlawed Kurdistan Workers Party (PKK), which has carried out a three-decade insurgency, mainly in Turkey's largely Kurdish southeast. Thirteen people have been detained.
"Sooner or later, we will have our vengeance. This blood will not be left on the ground, no matter what the price, what the cost," Soylu said in a speech at a funeral at the Istanbul police headquarters for five of the officers killed. President Tayyip Erdogan was present but did not speak, although he greeted and hugged some of the family members.
Soylu also warned those who would offer support to the attackers on social media or elsewhere, comments aimed at pro-Kurdish politicians the government accuses of having links to the PKK, which is designated as a terrorist organization by the United States, Europe and Turkey.
"To those trying to defend the perpetrators from podiums, over the media or internet, and trying to make up excuses. There is no excuse for this ... Know this: the blade of the state stretches far and wide."
In recent months, thousands of Kurdish politicians have been detained including dozens of mayors and the leaders of the Peoples' Democratic Party (HDP), parliament's second-biggest opposition party, accused of links to the PKK.
The crackdown against Kurdish politicians has coincided with widespread purges of state institutions following a failed coup in July that the government blames on followers of a U.S.-based Muslim cleric. Turkey says the measures are necessary to defend its security. Rights groups and some Western allies accuse it of ignoring the rule of law and trampling on freedoms.
In a statement, the pro-Kurdish HDP condemned the attack and urged the government to end what it called the language and politics of "polarization, hostility and conflict."
RIOT POLICE AND PARK
Soylu, the interior minister, said the first explosion, which came around two hours after the match between Besiktas and Bursaspor, was at an assembly point for riot police. The second came as police surrounded the suicide bomber in the nearby Macka park.
Thirty-eight people died, including 30 police and seven civilians, he said. One person remained unidentified.
A total of 155 people were being treated in hospital, with 14 of them in intensive care and five in surgery, Health Minister Recep Akdag told a news conference.
Flags flew at half mast, and Sunday was declared a day of national mourning. A march against terrorism had been called in Istanbul.
President Erdogan canceled a planned trip to Kazakhstan, his office said. Erdogan had earlier described the blasts as a terrorist attack on police and civilians. He said the aim of the bombings, after a match attended by thousands, had been to cause maximum casualties.
"Nobody should doubt that with God's will, we as a country and a nation will overcome terror, terrorist organizations ... and the forces behind them," he said in a statement.
Deputy Prime Minister Numan Kurtulmus said Turkey's allies should show solidarity with it in the fight against terrorism, a reference to disagreements with fellow NATO member Washington over Syria policy. The United States backs the Syrian Kurdish YPG in the fight against Islamic State. Turkey says the militia is an extension of the PKK and a terrorist group.
In addition to the Kurdish insurgency, Turkey is battling Islamic State as a member of the U.S.-led coalition against the jihadist group. Less than a week ago, Islamic State urged its supporters to target Turkey's "security, military, economic and media establishment."
'MY SON WAS MASSACRED'
Video purported to show the father of one of the victims, a 19-year-old medical student who had been in Istanbul for a weekend visit, went viral on social media in Turkey.
"I don't want my son to be a martyr, my son was massacred," the footage showed the father saying. "His goal was to be a doctor and help people like this, but now I am carrying him back in a funeral car."
Security remained tight in Istanbul, with police helicopters buzzing overhead in the Besiktas district near the stadium.
NATO Secretary-General Jens Stoltenberg condemned what he described as "horrific acts of terror," while European leaders also sent messages of solidarity. The United States condemned the attack and said it stood with its NATO ally.
The bombings come five months after Turkey was shaken by a failed military coup, in which more than 240 people were killed, many of them in Istanbul, as rogue soldiers commandeered tanks and fighter jets in a bid to seize power.
Istanbul has seen several other attacks this year, including in June, when around 45 people were killed and hundreds wounded as three suspected Islamic State militants carried out a gun and bomb attack on its main Ataturk airport.