A suicide car bomb in central Turkey has killed 13 soldiers aboard a bus and wounded 56 more, officials say.

The blast destroyed the bus carrying soldiers visiting a local market in the city of Kayseri. An army spokesman said civilians may also have been injured.

No group has admitted carrying out the attack, but Turkish officials say it bears the hallmarks of the outlawed Kurdistan Workers Party (PKK).

It comes a week after 44 people were killed in a PKK attack in Istanbul.

Regional governor Suleyman Kamci said the blast in Kayseri, a usually calm industrial hub in Central Anatolia, was carried out by a suicide bomber parked next to the bus near the entrance to Erciyes University. The soldiers were said to be on leave from a nearby military base.

Seven people have been arrested in connection with the blast

Images from the scene showed the bus reduced to a smouldering wreck with a massive hole punched in one side.

Turkish Deputy Prime Minister Numan Kurtulmus said the materials used were similar to those used in Istanbul.