Nurses fled a hospital as a powerful earthquake shook northeast Thailand.

Staff of the Fort Suranari Hospital escaped the building after it shook from the violent tremor in Nakhon Ratchasima province.

A janitor named Nareekarn In-ngam, 44, said: 'I was cleaning the fire exit on the eighth floor when suddenly, it felt like the world was spinning. I thought I was just dizzy. Then I saw nurses fleeing in panic.

'When I looked out the window, I noticed the doors shaking all over the building. That's when I realised that it was an earthquake. I ran down the fire exit because I was terrified of getting stuck in the lift. By the time I reached the first floor, my legs were shaking.'

The magnitude 7.7 quake sparked carnage across the capital Bangkok, with Thai Prime Minister Paetongtarn Shinawatra declaring the city an emergency zone.

The US Geological Survey said the tremor struck at a depth of 10 kilometres (six miles), and was centred in Myanmar, around 50 kilometres (30 miles) east of Monywa City.