Twenty-five buildings have collapsed, including a six-storey hotel in the city of Van, where journalists and aid workers were staying, officials said.

Emergency workers said 23 people had been rescued alive but that up to 100 more remained unaccounted for. The magnitude 5.7 earthquake struck 16 km (9 miles) south of the city of Van at 1923 GMT, the US Geological Survey said.

Television footage showed panicked people running through the streets of Van and ambulances rushing through the city with their sirens wailing. Medical staff treated one unconscious person lying on an ambulance stretcher.

Last month, a 7.2-magnitude quake in the same area killed 600 people. There have been hundreds of aftershocks since that disaster and thousands of people are still camping out in tents in freezing conditions in the area. All but three of the buildings which toppled in Wednesday's quake were empty, Turkey's deputy prime minister said, as they had been evacuated following the 23 October tremor.