ISTANBUL -- A car bomb blast killed 13 Turkish troops and wounded 55 people, most of them military personnel, in the central Anatolian province of Kayseri on Saturday morning, according to official figures.

In a statement, the Turkish armed forces said the car bomb went off at 8:45 a.m. and targeted on-leave military personnel from the Kayseri Commando Brigade.

The army said 48 troops were wounded and said civilian citizens also may have been hurt in the "treacherous act."

Speaking in Kayseri shortly after the blast, Interior Minister Suleyman Soylu said a total of 55 people had been wounded, and that six were in critical condition.

"We are determined in our fight against terrorism," the minister said.

Speaking beside him at a joint news conference, Turkish chief of staff Hulusi Akar vowed to continue the "fight against terrorists inside and outside the country" until "every last terrorist is neutralized."

There was no claim of responsibility for the attack.

The state-run Anadolu Agency said the car bomb went off at an entrance gate of Erciyes University, hitting a public-transportation bus that included on-leave soldiers among its passengers.

Images taken moments after the explosion showed a smoking public bus, still in flames, with its windows blown open and its interior blackened.

The blast comes a week after a car bomb struck riot police posted outside a soccer stadium in Istanbul after a match. That attack killed 44 people, mostly police officers, and wounded scores of others. Kurdish militants, who tend to target military and police, claimed the Istanbul attack.

Turkey is facing a range of security challenges including renewed conflict in the predominantly Kurdish southeast. Turkey is a member of NATO and partner in the U.S.-led coalition against the Islamic State group, which has been blamed for attacks in Turkey.

A state of emergency was declared after a July 15 coup attempt.

Speaking about the Kayseri explosion, Vice Prime Minister Veysi Kaynak said in remarks broadcast on NTV that "treacherous factions" had taken aim at commandos from the Kayseri Airforce Brigade, who had been "training exclusively for the safety of our people."

Turkey's prime ministry office imposed a temporary blackout on coverage of the explosion and urged media to refrain from publishing anything that may cause "fear in the public, panic and disorder and which may serve the aims of terrorist organizations."