Gaziantep, Turkey: More than 25 people were wounded when an explosion hit a bus in the central Turkish city of Kayseri on Saturday, local hospital sources said, although the death toll was still unclear.

Hospital sources earlier confirmed that there were dead and wounded from the blast, which hit a bus carrying off-duty soldiers and civilians near the campus of a university.

Ambulances were sent to the area after the explosion, the sources said.

There were dead and wounded from the blast, local hospital sources confirmed, but they were not able to immediately confirm the numbers involved.

The blast occurred as the bus passed by a car believed to be packed with explosives, Turkey’s Dogan news agency said.

It happened near a bus stop at the campus of Erciyes University in Kayseri, broadcaster NTV reported.

On Dec. 10 a twin bombing claimed by Kurdish militants outside an Istanbul soccer stadium killed more than 40 people and wounded more than 100.

Turkey faces multiple security threats including spillover from the fight against Islamic State in northern Syria, where it is a member of a US-led coalition against the militant group.

It also faces regular attacks from Kurdish militants, who have been waging a three-decade insurgency for autonomy in largely Kurdish southeast Turkey.