Turkey's Prime Minister Binali Yildirim says authorities are in no position to verify whether a child suicide bomber was responsible for a blast that killed at least 54 people on Saturday, reversing an earlier assertion by President Recep Tayyip Erdogan.

"We are not in a position to verify anything about who the perpetrator was - if it was a child, an adult, or for which organisation," Yildrim told reporters in Ankara on Monday, referring to the suicide attack at a wedding in the city of Gaziantep.

"We do not have a clue about who the perpetrators behind the attack were," he added. "Early information on who did the attack, in what organisation's name, is unfortunately not right," he said.

Erdogan had said on Sunday that a child suicide bomber aged "between 12 and 14" was responsible for the attack, and that the bombing in Gaziantep had been "perpetrated by Daesh".

Daesh is another name for the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) armed group.

It was not immediately known what new evidence had prompted Yildrim to backtrack so completely on the president's earlier assertions.

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Earlier on Monday, the Turkish daily Hurriyet, citing security officials who examined CCTV footage from the area of the attack, said the suspected child suicide bomber was accompanied to the scene of the attack by two adults.

The two adults "fled in a vehicle just before the blast", Hurriyet reported.

A Turkish security official told the Reuters news agency on Monday that they were investigating the possibility that adult fighters could have placed the explosives on the child without his or her knowledge, and detonated the device remotely, or that a mentally disabled child was duped into carrying the device, a tactic seen elsewhere in the region. 

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"It could be that someone was loaded with explosives without even being aware of it and it may have been detonated remotely," the official said, adding that a search was under way for suspects who may have played a reconnaissance role.

The Hurriyet daily said that DNA tests were under way to ascertain the identity and nationality of the bomber.

'Same device'

The device used in Saturday's bombing, which contained scraps of metal, was the same type used in 2015 attacks on a peace rally in Ankara and on the border district of Suruc, Turkish media also reported on Monday, citing security sources.

Both the Ankara and Suruc attacks were blamed on ISIL, reinforcing the suspicion that the armed group was also behind the Gaziantep bombing, the official said.

The group has targeted Kurdish gatherings in Turkey for more than a year. The Ankara bombing was the deadliest of its kind in Turkey, killing more than 100 people.

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Meanwhile, three more people receiving treatment at hospitals after the attack in Gaziantep died from their wounds in the early hours of Monday. 

A total of 66 wounded are still receiving treatment at hospitals in the province, with 14 in a critical condition.

"Daesh should be completely cleansed from our borders and we are ready to do what it takes for that," Foreign Minister Mevlut Cavusoglu said at a news conference in Ankara.

Cavusoglu said Turkey, a member of NATO and the US-led coalition against ISIL, had become the "No.1 target" for ISIL fighters because of its work to stop recruits travelling through Turkey across its over 800km border into Syria to join the armed group.

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Source: Al Jazeera and agencies