Huge 7.7 earthquake in Myanmar sparks panic in Bangkok 800 miles away as dozens trapped after tower collapses

Footage shared online showed builders fleeing the collapsing skyscraper in Thailand.

The number of casualties remains unclear but 43 people were trapped inside, according to police. Seven managed to escape.

A senior police officer said he heard people calling for help as he arrived to inspect the site.

The earthquake hit in Myanmar, to the north-west of Thailand, at around 6.20 UK time, which is early afternoon local time. A mosque is said to have collapsed in the country's southern Bago region, with three casualties reported.

Dozens more deaths caused by collapsing buildings were reported by the local media in Myanmar. A local official described a hospital in Mandalay as a "mass casualty area".

Tremors were also felt in China, Vietnam and India.

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The earthquake's epicentre was ten miles northwest of the Burmese city of Sagaing, near Mandalay.

A second earthquake - smaller but still large - of 6.4 on the Richter scale took place a few minutes after the first.

The USGS said that buildings in Myanmar and Thailand are particularly vulnerable to earthquakes. The agency said: "The population in this region resides in structures that are vulnerable to earthquake shaking, though resistant structures exist.

"The predominant vulnerable building types are informal (metal, timber, GI etc.) and unreinforced brick masonry construction."

The region suffers fairly regular earthquakes as it is close to seismic fault lines, but this is the strongest to hit for decades. Nearly all earthquakes felt in Thailand take place in Myanmar.

Elsewhere in Bangkok, the earthquake was forceful enough to send water sloshing out of pools, some high up in high-rises, as the tremor shook.

One resident said she was "very nervous" and "very panicked".

She added: "In my apartment I just see some cracking on the walls and water splashed out of swimming pools and people just yelling.”

Fraser Morton, a tourist from Scotland, who was in a shopping centre when the earthquake took place, said the event sparked "lots of chaos".

"All of a sudden the whole building began to move, immediately there was screaming and a lot of panic," he said.

"I just started walking calmly at first but then the building started really moving, yeah, a lot of screaming, a lot of panic, people running the wrong way down the escalators, lots of banging and crashing inside the mall."

He sought refuge in Benjasiri Park, away from the tall buildings."I got outside and then looked up at the building and the whole building was moving, dust and debris, it was pretty intense," he said.

Alarms went off in buildings as the earthquake hit around 1.30pm local time, and startled residents were evacuated down staircases of high-rise buildings and hotels in densely populated central Bangkok.

They remained in the streets, seeking shade from the midday sun in the minutes after the quake.

The quake was forceful enough to send water sloshing out of pools, some high up in high-rises, as the tremor shook.

The extent of the damage was less clear in Myanmar, where the government has not commented yet.

Footage shared online shows the the Ava Bridge, a large suspension bridge built in 1934, collapsing. Mandalay international airport also appears to be closed.

In the capital Naypyitaw, the earthquake damaged religious shrines, sending parts toppling to the ground, and some homes.

There were no immediate reports of the effect of the earthquake in Myanmar, which is in the middle of a civil war.

Thailand's Department of Disaster Prevention said the earthquake was felt in almost all regions of the country. The Prime Minister is said to be holding an emergency meeting to coordinate the response to the earthquake.