An explosion Monday in Turkey’s southeastern city of Suruc near the Syrian border killed 28 people and sent nearly 100 others to the hospital, Turkish officials said.

The prime minister’s office gave the casualty toll in a phone call to The Associated Press.

There was no immediate claim of responsibility for the midday blast.

Suruc is just across the border from the Syrian city of Kobani, the scene of fierce battles between Kurdish groups and the Islamic State group. Kobani was the Islamic State group’s biggest defeat last year since the militants established control over large swathes of Iraq and Syria. The city has become a symbol of Kurdish resistance.

A second bomb went off Monday south of Kobani near a Kurdish militia checkpoint on the road to Syria’s largest city of Aleppo, according to a Kurdish official in Kobani, Idriss Naasan. It caused minor damage and no casualties, he said.

DHA said the blast in Suruc occurred at a cultural center while a political group was holding a news conference on Kobani’s reconstruction. News reports said 300 people from the Federation of Socialist Youths were staying at the cultural center and were preparing to travel to Kobani to help with the rebuilding.

Kobani was also the scene of surprise IS attacks last month that killed more than 200 people.