Turkish President Tayyip Erdogan on Monday condemned those responsible for a "terrorist attack" that killed 30 people and wounded more than 100 others in the town of Suruc in southern Turkey, near the Syrian border.
The attack was the worst in Turkey in more than two years.
Turkish officials said the attack earlier on Monday outside an overcrowded cultural center may have been a suicide bombing by Islamic State militants. Erdogan was speaking at a joint news conference with the head of the Turkish Cypriot administration during an official visit to Nicosia. His comments were broadcast live by TRT television.
The blast took place in Suruc, across from Kobane in northern Syria, which was the scene of fierce battles earlier this year between Kurdish fighters, backed by U.S.-led airstrikes, and the Islamic State extremist group.
"We are certain it was a suicide bomber," Izzettin Kucuk, the governor of Sanliurfa province, said, according to Hurriyet newspaper.
Turkey's pro-Kurdish People's Democratic Party (HDP) blamed the attack on Islamic State militants and called for the government to ensure the safety of all citizens.
Videos on social media showed the moment of the attack in Suruc. The youth were chanting slogans and holding banners when an explosion ripped through the crowd, leaving bodies on the ground.
A community meeting was being hosted in the garden of the cultural center. It was focused on rebuilding Kobane, which suffered extensive damage as the Kurds fought off an Islamic State assault and siege that lasted several months.
Prime Minister Ahmet Davutoglu has dispatched three senior ministers to the scene.
Local hospitals issued calls for blood donations.
Across the border in Kobane, two people were killed in a car bombing near a checkpoint of the Kurdish People's Protection Units (YPG), Kurdish official Idriss Nassan said.
In 2013, the border town of Reyhanli was attacked, leaving at least 50 people dead, in what was described as the most deadly assault in Turkey.