At least 20 people have died at one of Myanmar’s major hospitals in the capital of Naypyidaw, a doctor has said.

“About 20 people died after they arrived at our hospital so far. Many people were injured,” the doctor at the 1,000-bed general hospital told Agence France-Presse (AFP).

The doctor requested anonymity, with casualty numbers emerging slowly from Myanmar, where there restricted access for journalists and aid workers.

Authorities in Myanmar will push for access to disaster relief and humanitarian aid, state media has said.

Myanmar has began investigations into the damage and will conduct rescue operations as soon as possible.

Authorities are pushing for humanitarian aid access, the military-controlled Global New Light of Myanmar said, as humanitarian organisations express fears about the country’s history of denying aid.

At least eight people were killed after a massive earthquake of 7.7 magnitude struck Myanmar and neighbouring Thailand on Friday, as rescuers raced to free dozens trapped under the rubble of a collapsed high-rise building under construction in Bangkok.

The quake struck at a depth of 10km, about 17.2km from Myanmar’s second-largest city of Mandalay, according to the United States Geological Survey (USGS).

Three people died in the town of Taungoo in Myanmar after a mosque partially collapsed, according to reports. Two others died and 20 were injured after a hotel collapsed in Aung Ban.

Fears have been raised that Myanmar’s military junta could deny aid to regions of the country ravaged by the earthquake – something they have a history of doing.

Amnesty International’s Myanmar researcher, said: “This earthquake could not come at a worse time for Myanmar.

“Central Myanmar, which is believed to be the epicentre of the earthquake, has been ravaged by military air strikes and clashes between resistance groups and the military.

“Myanmar’s military has a longstanding practice of denying aid to areas where groups who resist it are active. It must immediately allow unimpeded access to all humanitarian organizations and remove administrative barriers delaying needs assessments.”

Bryony Lau, deputy Asia director at Human Rights Watch, said the Myanmar junta has “an appalling history of blocking aid following natural disasters, depriving people of assistance and increasing the suffering of communities affected”.

Fraser Morton, a tourist from Scotland, was in one of Bangkok’s malls when the earthquake struck.

“All of a sudden the whole building began to move. Immediately there was screaming and a lot of panic. 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 said.

Thousands of people poured into Benjasiri Park from nearby shopping malls, high rises and apartment buildings along Bangkok’s busy Sukhumvit Road.

“I got outside and then looked up at the building and the whole building was moving, dust and debris, it was pretty intense,” Morton said. “Lots of chaos.”

Voranoot Thirawat, a lawyer working in central Bangkok, said her first indication that something was wrong came when she saw a light swinging back and forth. Then she heard the building creaking as it moved back and forth.

She and her colleagues ran down 12 flights of stairs. “In my lifetime, there was no earthquake like this in Bangkok,” she said.

Blood is in high demand in Myanmar’s hospitals as medics scramble to look after the casualties following the massive earthquake earlier today.

The worst-hit areas of Mandalay, Sagaing, and Naypyitaw are struggling to keep up with the amount of blood needed, Myanmar’s military government spokesperson Maj. Gen. Zaw Min Tun said.

He urged blood donors to contact hospitals as soon as possible.

The Independent’s travel correspondent Simon Calder reports:

City transport in Bangkok has been suspended on two subway lines and on the BTS Skytrain to and from the main international airport.

Worapa Angkhisirisap, director of the Tourism Authority of Thailand in London said: “MRT Blue and Purple Lines are temporarily suspended. BTS Skytrain is also temporarily suspended due to emergency protocols.”

In addition, the rail link to the northern suburb of Rangsit “may face delays due to structural inspections on elevated tracks”.

But, she said, both Bangkok’s airports are operating normally, with no disruption to flights.