Four Killed In Istanbul Suicide Bombing

At least four people have been killed after a suicide bombing in Istanbul's main shopping street.

The blast happened outside a local government office on Istiklal Caddesi, a thoroughfare on the European side of the city lined with shops, restaurants and foreign consulates.

Two American-Israelis and an Iranian are confirmed dead.

Police have sealed off part of the street which adjoins Taksim Square and a forensic team is present.

Television footage showed people running from the scene.

The attacker was deterred from an initial target by police and detonated the bomb "out of fear", an official said.

"This is a suicide attack, a terrorist attack," Governor Vasip Sahin said from the scene, confirming the bomber was also killed.

Another 36 people had been wounded, seven of them seriously.

Twenty of those hurt are foreigners: 11 Israelis, one each from Iceland, Germany, Dubai and Iran, and five Irish nationals of Algerian descent, including two children.

Ireland's foreign minister, Charlie Flanagan, said he was "deeply saddened", adding: "I have spoken to Ambassador Brendan Ward in Turkey and can confirm that we are aware of a number of Irish citizens among the injured.

"An Embassy official is on the ground in Istanbul to provide consular assistance. Anyone with concerns for Irish citizens please ring 01 4082000 or Embassy Ankara on 0090 312 4591000."

No group has claimed responsibility, but Turkish officials said evidence pointed to Islamic State or the outlawed Kurdistan Workers' Party (PKK).

Turkey is on edge after two suicide bombings in the capital, Ankara, including one earlier this month that killed 37 people. Another attack there in February killed 29 people.

Both of those bombings were claimed by the Kurdistan Freedom Falcons (TAK) - an off-shoot of the PKK.

Five people are in custody over the latest Ankara attack, which the TAK said was to avenge Kurds killed during an ongoing military offensive in the southeast against the PKK.

Following Saturday's bombing, Turkish Prime Minister Ahmet Davutoglu warned "no centre of terrorism will reach its aim with such monstrous attacks".