The Kurdish youths were chanting and holding a banner when the bomber blew himself up.
At least 28 people were killed in the blast.
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The BBC reported:
A suspected suicide attack has killed at least 28 people and wounded nearly 100 others in the Turkish town of Suruc near the Syrian border.
The blast occurred in the garden of a cultural centre at about 09:00 GMT, the interior ministry said.
Hundreds of young people were staying there to assist in rebuilding work in the nearby Syrian town of Kobane.
Turkish officials have said initial evidence indicates it was a suicide attack by the Islamic State (IS) group.
Turkey’s President Recep Tayyip Erdogan has condemned the bombing.
Suruc houses many refugees who have fled the fighting in Kobane between IS militants and Kurdish fighters.