At least five people, including the attacker, have been killed, and at least 36 others injured after a suicide bombing rocked the main shopping street in central Istanbul, according to the local governor.
Photos from the scene on Istiklal Street in Taksim district that have emerged online show badly maimed bodies and body parts lying in the street. Dozens of ambulances and emergency workers are on the spot.
Of the 36 wounded, at least seven are in serious condition, Governor Vasip Sahin said in a live statement on CNN Turk.
Twelve of the injured were foreign citizens. “Six Israelis, two Irish, a German, an Icelander, an Iranian and a UAE national, injured during the attack, are being treated in five hospitals,” the Health Ministry statement says as cited by RIA Novosti.
One Turkish official said the terrorist wanted to target a more crowded place, but was deterred by the presence of police.
"The attacker detonated the bomb before reaching the target point because they were scared of the police,” the unnamed official said as quoted by Reuters.
Turkish officials have also indicated there is fresh evidence suggesting the attacker may have been from Islamic State or the PKK, Reuters reports.
According to unconfirmed reports, Turkish police are focusing on three possible male suspects with two of them being from the southern city of Gaziantep near the Syrian border, Reuters says.
Two victims of the attack are foreigners: an Iranian and an Israeli, Turkish officials told Reuters.
Israeli Prime Minister Benjamin Netanyahu said that at least two Israeli citizens were killed by the blast adding that one more Israeli may also have lost the life during the attack.
Earlier reports citing an unnamed official suggested Kurdish militants were behind the attack.
Turkish Prime Minister Ahmet Davutoglu called the attack “inhumane” and vowed to continue the struggle against "centers of terrorism".
"No center of terrorism will reach its aim with such monstrous attacks. Our struggle will continue with the same resolution and determination until terrorism ends completely," Davutoglu said in a statement, according to Reuters.
Diplomats have begun expressing their solidarity with the Turkish authorities.
"I strongly condemn this despicable and cowardly act that has caused the death of several people," French Foreign Minister Jean-Marc Ayrault said in a statement, as quoted by Reuters.
Iranian Foreign Minister Mohammad Javad Zarif who is on an official visit to Istanbul said the attack showed “the ugly face of terrorism.”
The attack was also condemned by Turkey's Peoples' Democratic Party (HDP), a Kurdish-rooted opposition party.
"Just as in the Ankara attack, this is a terrorist act that directly targets civilians. Whoever carried out this attack, it is unacceptable and inexcusable,” the HDP said as cited by Reuters.
Tensions in Turkey have been running high over the past few months, with terror attacks on the rise.
This latest bombing comes about a fortnight after the Turkish capital Ankara was hit by a grenade-and-gun attack, carried out by two female terrorists. Last month, at least 28 people were killed and 61 wounded in a car explosion in Ankara. The blast targeted military personnel near the parliament building.