ISTANBUL, Turkey (AFP) — Turkish authorities scrambled Monday to identify a child suicide bomber acting on the orders of Islamic State jihadists who killed 54 people including several children at a Kurdish wedding close to the Syrian border.

Foreign Minister Mevlut Cavusoglu said the IS group needed to be completely pushed out of the border zone inside Syria, amid Turkish media reports of an Ankara-backed offensive by rebels against the group.

The attack late Saturday on a crowded street wedding in the city of Gaziantep was the latest in a devastating series of bombings in Turkey at a time when the country is riven by internal upheaval and shaken by the civil war in neighbouring Syria.

President Recep Tayyip Erdogan said the bomber was aged “between 12 and 14” and that initial findings showed it had been “perpetrated by Daesh (IS)”.

Media said the majority of those dead were children or teenagers, with 29 of the 44 victims identified so far aged under 18. At least 22 victims were under 14, a Turkish official added.

There were no further details on the bomber, but Erdogan said IS had been trying to “position itself” in Gaziantep, which lies just 60 kilometres (37 miles) north of Syria and is a major hub for refugees from the more than five-year civil war.

The death toll rose to 54 after three more died in hospital in the early morning, the Dogan news agency reported.

Sixty-six people were still in hospital, 14 of them in a serious condition.

– ‘Fight IS to the end’ –

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

It is possible that the bomber had come over the border from Syria but IS is also known to have built homegrown cells inside Turkey in Gaziantep and even Istanbul, wrote its well-connected columnist Abdulkadir Selvi.

He said Turkish security forces believed the attack had been timed as retaliation by jihadists for offensives both by Kurdish militias and pro-Ankara Syrian opposition forces against IS in Syria.

“There’s a fight against IS but we are paying the price,” he wrote.

Without explicitly confirming the rebel offensive, Cavusoglu said Turkey backed anyone fighting against IS and would itself fight the group “to the end”.

“Our border must be completely cleansed from Daesh,” he said in televised remarks, using an Arabic acronym for the IS group.

“It is our most natural right to fight at home and abroad against such a terrorist organisation.”

– ‘All the dead Kurds’ –

The leader of the pro-Kurdish Peoples’ Democratic Party (HDP) Selahattin Demirtas said in a statement that “all of those killed were Kurds”.

The bride and groom — a couple from the strongly Kurdish region of Siirt to the southeast — were rushed to hospital but not seriously wounded.

The attack followed a string of strikes blamed on IS and Kurdish militants in recent months but was the deadliest so far this year and first significant jihadist action in Turkey since a failed July 15 coup.

Erdogan said that in his view all “terror” groups are the same, be it the Islamic State group, the outlawed Kurdistan Workers Party or supporters of US-based preacher Fethullah Gulen whom he blames for the coup.

Hurriyet said the type of bomb used — stuffed with scraps of metal — was similar to explosives used in previous suicide bombings against pro-Kurdish gatherings blamed on IS in the border town of Suruc and at Ankara train station last year.

The authorities were also looking for two individuals said to have accompanied the suspected suicide bomber into the wedding party but who then left the scene.

All 44 victims identified so far were laid to rest in harrowing ceremonies in Gaziantep on Sunday with relatives throwing themselves on the coffins in desperation, an AFP correspondent said.

The hillside graveyard was pock-marked before the ceremony with the holes of dozens of freshly dug graves for the victims.

One mother, Emine Ayhan, lost four of her five children in the bombing while her husband is in intensive care, the Yeni Safak daily said.

According to the list of victims in Turkish media, the youngest — named as Gurbet Akcan and Muhammet Yagiz — were both aged four. There was one Syrian among the dead, Husam Cuma, aged seven.