At least 40 people were killed and 100 others injured after explosions shook a Turkish town on Saturday near the border with Syria, Turkish Interior Minister Muammer Guler said.

Earlier reports put the toll of the attack at 18 killed and some 20 injured.

The number of casualties may continue to increase, as many of the injuries are severe, said Guler.

Initial reports said four blasts occurred near the municipality building and post offices in the town of Reyhanli in the southern Turkish province of Hatay.

In his initial comments, Turkish Prime Minister Recep Tayyip Erdogan said "those who cannot digest this new period (of settlement process with PKK) and the atmosphere of freedom in our country can be involved in such attacks."

The PKK militants have recently started to withdraw from Turkey, after months-long talks between Ankara and the armed group.

"Hatay is a province with sensitivities. We have Syrian guests there. There can also be some who cannot digest this [presence of Syrian refugees]," said Erdogan.

Turkish Foreign Minister Ahmet Davutoglu on Saturday slammed the incident as an act of "provocation," saying "there may be some powers who want to sabotage peace in Turkey."

Local reports said tensions have already been high in the area for a couple of weeks. Lately, there was a gang fight between Syrian refugees and Turkish youths in Reyhanli.

Turkey is facing an influx of Syrian refugees with the worsening situation in Syria.

Earlier in May, one Turkish border guard was killed and six others were wounded in a clash at the Syrian border.