“According to the first information, we consider it a terrorist attack due to the detonation of a bomb by a female attacker,” Oktay told reporters, according to Agence France-Presse (AFP).
“The Turkish authorities will find out who is behind this attack, whoever it is, even if you have to go to the other side of the world,” the official said.
The attack took place at 4:20pm local time today (1:20pm in Lisbon) on Istiklal Avenue in the business district of Istanbul, Turkey’s largest city and the country’s economic capital.
On live television, Turkish President Recep Tayyip Erdogan condemned the “heinous attack”, saying “initial observations” suggested it was a terrorist attack in which “a woman was involved”.
No claims have yet been made for the attack.
“The perpetrators of this heinous attack will be hidden. Let our people rest assured that they will be punished,” he said.
Five prosecutors have already been appointed to investigate the explosion, according to state news agency Anadolu.
The Supreme Council of Radio and Television, Turkey’s media watchdog, imposed a temporary moratorium on reporting on the blast – preventing broadcasters from showing videos of the moment of the blast or its aftermath.
The same body has already imposed similar bans in the past following attacks and accidents.
In the images broadcast on social networks, the moment of the explosion is heard, accompanied by flames that immediately trigger the movement of panic.
A large black crater is visible in these images, with several bodies on the ground nearby.
Other footage showed ambulances, fire engines and police at the scene.
Between 2015 and 2017 Turkey suffered a series of deadly attacks by the Islamic State group and Kurdish groups.
During this period, Istiklal Avenue was attacked by the Islamic State group, killing nearly 500 people and injuring more than 2,000.
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