Istanbul (Turkey) (AFP) - Turkey’s interior minister accused the outlawed Kurdistan Workers’ Party (PKK) on Monday of responsibility for a bombing in a busy Istanbul street that killed six people and wounded scores, saying more than 20 people have been arrested.

Turkish President Recep Tayyip Erdogan landed in the Indonesian resort island of Bali for a G20 summit of the world’s leading economies shortly after his government accused the PKK of being behind Sunday’s blast, which wounded 81.

He had called the bombing a “vile attack” before leaving for the summit and said it had a “smell of terror.”

The explosion tore through Istiklal Street, a popular shopping destination for locals and tourists, on Sunday afternoon. No individual or group has claimed the attack.

“The person who planted the bomb has been arrested,” interior minister Suleyman Soylu said in a statement broadcast by the official Anadolu news agency in the early hours of Monday.

He added that 21 others were also detained.

“According to our findings, the PKK terrorist organisation is responsible,” he said.

The PKK, blacklisted as a terrorist group by Ankara as well as its Western allies, has kept up a deadly insurgency for Kurdish self-rule in southeastern Turkey since the 1980s.

Soylu also accused PKK-affiliated Kurdish militants who control most of northeastern Syria and who are deemed as “terrorists” by Ankara of being responsible for the attack.

“We believe that the order for the attack was given from Kobane,” he said, referring to a city near the Turkish border. It was also the site of a 2015 battle between Kurdish militants and Islamic State jihadists, who were driven out after more than four months of fighting.

Regularly targeted by Turkish military operations, the PKK is at the heart of a tussle between Sweden and Turkey, which has been blocking Stockholm’s entry into NATO since May, accusing it of leniency towards the group.

“We believe that it is a terrorist act carried out by an attacker, whom we consider to be a woman, exploding the bomb,” Turkey’s vice president Fuat Oktay said.

Justice minister Bekir Bozdag told Turkish news channel A Haber that a woman “had been sitting on one of the benches for more than 40 minutes, and then she got up”, leaving a bag.

“One or two minutes later, an explosion occurred,” he said.

“There are two possibilities,” he said. “There’s either a mechanism placed in this bag and it explodes, or someone remotely explodes (it).”

“All data on this woman are currently under scrutiny,” he said.

Soylu’s announcement did not add any details about the woman or the suspects arrested.

Istiklal Avenue reopened early on Monday morning.

Mecit Bal, who runs a small shop a few metres from the scene, said his son was working at the time of the blast.

“My son was there. He called me and said an explosion happened. He will not go back to work today. He is psychologically affected,” he told AFP.

- Panic, chaos -

Turkish cities have been struck by Islamists and other groups in the past.

Istiklal Street was hit during a campaign of attacks in 2015-2016 that targeted Istanbul and other cities, including Ankara.

Those bombings were mostly blamed on the Islamic State group and outlawed Kurdish militants, and killed nearly 500 people and wounded more than 2,000.

Sunday’s explosion occurred shortly after 4:00 pm (1300 GMT) in the famous shopping street.

Helicopters flew over the city centre after the attack. Police established a large security cordon to prevent access to the area for fear of a second explosion.

Images posted on social media showed the explosion was followed by flames and immediately triggered panic, with people running in all directions.

Several bodies were seen lying on the ground nearby.

“I was 50-55 metres away, suddenly there was the noise of an explosion. I saw three or four people on the ground,” witness Cemal Denizci, 57, told AFP.

“People were running in panic. The noise was huge. There was black smoke,” he said.

- Condemnation -

Istiklal, in the historic district of Beyoglu, is one of the most famous arteries of Istanbul. It is entirely pedestrianised for 1.4 kilometres, or about a mile.

Criss-crossed by an old tramway and lined with shops and restaurants, it attracts large crowds at the weekend.

Many stores closed early in the neighbouring district of Galata, while some passers-by, who came running from the site of the explosion, had tears in their eyes.

A massive deployment of security forces barred all entrances and rescue workers and police could be seen.

Turkey’s radio and television watchdog, RTUK, placed a ban on broadcasters showing footage of the blast, a measure previously taken in the aftermath of extremist attacks.

Access to social media was also restricted after the attack.

A reaction came quickly from Greece, which “unequivocally” condemned the blast and expressed condolences to the government and people of Turkey.

The United States also denounced it, with White House Press Secretary Karine Jean-Pierre saying: “We stand shoulder-to-shoulder with our NATO Ally Turkey in countering terrorism.”

French President Emmanuel Macron said in a message to the Turks: “We share your pain. We stand with you in the fight against terrorism”.

Ukrainian President Volodymyr Zelensky also tweeted in Turkish: “The pain of the friendly Turkish people is our pain.”