4 more suspects detained over Istanbul bombing attack: Turkish PM

ISTANBUL - Turkish police detained four more suspects on Wednesday over their links with the suicide bomber in Tuesday's Istanbul explosion, Turkey's Prime Minister Ahmet Davutoglu said.

One suspect was netted on Tuesday evening, hours after the attack.

Emerging from a meeting on security in Istanbul, Davutoglu told reporters that after a detailed investigation the authorities have detected the assailant's link with Islamic State (IS) and revealed some secret actors and important elements behind the attack.

"The assailant's link to Daesh has been determined but Daesh is an intermediary organization," the prime minister said, using the Arab name of the IS.

Davutoglu claimed that some countries are trying to drag Turkey into a fire circle. "We will reveal all these ties behind Daesh and we won't let Turkey be dragged into this circle," he added.

The prime minister vowed to reveal the "real actors" behind the IS which Turkey has said was behind last year's deadly bombings in the southeastern city of Suruc and the capital Ankara, and now in Istanbul.

He also confirmed that the Istanbul bomber entered into Turkey as a refugee.

Turkey's Dogan news agency said the bomber, identified as a 28-year-old Syrian national named Nabil Fadli, applied for asylum on Jan 5 in Istanbul, and the police are searching for the four other men who arrived with him.

Ten tourists were killed during the suicide bomb attack Tuesday at Istanbul's historic Sultanahmet Square, a popular tourist destination. Some 17 others were injured, including nine Germans, one Peruvian and seven Norwegians.

Ten Germans are confirmed dead, Turkish media reported, quoting a statement from Germany's Foreign Ministry.

The attack is a serious blow to Turkey's ailing tourism industry which has already been troubled due to Russia's travel ban following Ankara's downing of a Russian warplane in November.