A midday explosion in Turkey's southeastern city of Suruc near the Syrian border killed 28 people Monday 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 blast. 
  
A Turkish official, however, said authorities have evidence that the attack was a suicide bombing and suspect the Islamic State group was behind it.  He spoke on condition of anonymity because he was not authorized to speak on the record.
  
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, and 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 Idriss Naasan, a Kurdish official in Kobani. It caused minor damage and no casualties, he said.
  
The private Turkish news agency 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 center and were preparing to travel to Kobani to help with the rebuilding. 
  
Suruc hosts the largest refugee camp in Turkey, which has seen nearly two million Syrians cross its border to flee the fighting in their homeland. 
  
More than 220,000 people have been killed and at least a million wounded since Syria's crisis began in March 2011, according to the U.N.
  
Kobani was also the scene of surprise IS attacks last month that killed more than 200 people. (AP)