ISTANBUL — A child suicide bomber killed at least 51 people and wounded nearly 70 others at a Kurdish wedding party near Turkey’s border with Syria, President Recep Tayyip Erdogan said Sunday, decrying the attack as an apparent attempt by Islamic State extremists to destabilize the nation by exploiting ethnic and religious tensions.

“As of now, the preliminary conclusions by our governor’s office and the police establishment point to an attack by Daesh,” Erdogan said, using another common term for IS.

“It was clear that Daesh had such an organization in Gaziantep or was attempting to make room for itself in recent times,” he said.

The bombing late Saturday in Gaziantep was the deadliest attack in Turkey this year.

It comes amid ongoing struggles between the government and Kurdish militants linked to the outlawed Kurdistan Workers’ Party, known as the PKK, and as the country is still reeling from the aftermath of last month’s failed coup attempt, which the government has blamed on U.S.-based Muslim cleric Fethullah Gulen and his followers.

Erdogan said immediately after the Gaziantep attack, which he blamed on IS, that any strategy “meant to incite the citizens against each other along ethnic and religious lines will not work.”

Later, addressing the nation before Istanbul’s city hall, Erdogan said the attacker in Gaziantep was aged between 12 and 14. He said 69 people were wounded, with 17 of them in critical condition.

He again blamed the attack on the Islamic State, but there was no immediate claim of responsibility.

The pro-Kurdish political party HDP condemned the attack on the wedding, which it said was attended by many of its party members.