Police have concluded that the June 27 attacks, which claimed 17 lives, were staged by the separatist Kurdistan Workers' Party (PKK), Interior Minister Besir Atalay said Saturday, as he announced the arrest of several suspects.

Newspapers identified the bomber as Huseyin Tureli, a 26-year-old militant trained in PKK camps in neighbouring northern Iraq, who was among eight suspects whom an Istanbul court Saturday remanded to custody pending trial.

Tureli confessed to planting the bombs in a crowded pedestrian street in the residential neighbourhood of Gungoren and detonating them by mobile telephone, Hurriyet reported, without revealing its sources.

Tureli, who was accompanied by five accomplices at the scene, told the police they watched for 20 minutes after the second explosion and then walked away, the daily said.

As the first bomb drew a large crowd of onlookers, a second, more powerful device went off about 10 minutes later, killing 17 people, including five children and a pregnant woman.

More than 150 people were injured.

Footage from security cameras in the street and records of telephone calls between the suspects were instrumental in rounding them up, Hurriyet said.

The PKK took up arms for self-rule in Turkey's mainly Kurdish southeast in 1984, sparking a conflict that has claimed more than 37,000 lives.

Listed as a terrorist group by Ankara and much of the international community, the PKK has denied responsibility for the latest bombings.

The blasts were the deadliest attack on civilians in Turkey since 2003 when two sets of twin suicide bombings, blamed on Al-Qaeda, claimed 63 lives in Istanbul.

Prime Minister Recep Tayyip Erdogan has described the blasts as "the cost" of an intensified military crackdown against the PKK, both inside Turkey and in northern Iraq, where the rebels take refuge.

Following the blasts, Turkish warplanes bombed Tuesday a PKK base in the Qandil mountains in northern Iraq, a major PKK stronghold, killing an unspecified number of militants.

Some analysts have suggested the PKK leadership is in disarray and cannot control radical cells.

In January, the PKK apologised for a car bombing in the mainly Kurdish city of Diyarbakir which killed seven people, saying it was the work of militants who acted without the leadership's approval.