Bangkok. A 7.7 magnitude earthquake and an aftershock measuring 6.4 rocked Thailand and neighboring Myanmar on Friday, bringing down a high-rise building under construction in Bangkok and damaging historic buildings in Myanmar. Damage was also reported in China.

The quake struck in the early afternoon, sending people streaming out of buildings and seeking shelter anywhere they could find it from the blazing sun.

Myanmar's military-run government has declared a state of emergency in six regions.

The greater Bangkok area is home to more than 17 million people, many of whom live in high-rise apartments. While the epicenter was in Myanmar, the area is generally sparsely populated, and most houses are low-rise structures.

Bridge Collapse, Highway Damaged
In Mandalay, Myanmar’s second-largest city and close to the epicenter, the earthquake damaged part of the former royal palace and buildings, according to videos and photos released on Facebook social media.

In the Sagaing region, southwest of Mandalay, a 90-year-old bridge collapsed, and some sections of the highway connecting Mandalay and Myanmar’s largest city, Yangon, were damaged.

In the capital Naypyitaw, the quake damaged religious shrines, sending parts toppling to the ground.

Maj. Gen. Zaw Min Tun, a military government spokesperson, told state television MRTV that blood was in high demand in the hospitals in earthquakes-hit areas, especially Mandalay, Sagaing, and Naypyitaw.

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

‘Significant Damage’
The Red Cross said downed power lines are adding to challenges for their teams trying to reach Mandalay and Sagaing regions and southern Shan state.

“Initial reports from the ground suggest the earthquake has caused significant damage,” the Red Cross said. “Information on humanitarian needs is still being gathered.”

State of Emergency
A state of emergency has been declared in six regions and states in Myanmar by the military-run government.

State-run MRTV television said the government’s proclamation includes the capital Naypyitaw and Mandalay, after the earthquake and a strong aftershock, whose epicenter was near the country’s second-largest city.

Myanmar is in the midst of a civil war and many areas are not easily accessible and it was not immediately clear what relief efforts the military would be able to provide.

Many Missing in Bangkok Building Collapse
Thai emergency responders said at least two people have been found dead and an unknown number of others are still under the rubble of a collapsed building in Bangkok.

Rescue worker Songwut Wangpon, speaking at the scene of a tall pile of rubble that was once a high-rise building under construction, told reporters another seven people had been found alive.

Thailand’s Defense Minister Phumtham Wechayachai later said three people had been confirmed dead with 90 others missing following the building collapse.

The collapse of the multi-story structure sent a crane on top of it toppling to the ground and creating a massive plume of dust.

People Rush for Safety in Teeming Bangkok
People in the Silom business district of Bangkok evacuated office buildings and condominium towers along Rama IV Road and streamed into nearby Lumphini Park. The sidewalks filled with work crews with neon green shirts, along with other workers in hard hats and blue and green uniform shirts.

Along the walkways of the park and the sidewalks of Silom and nearby Sathon, people in business attire and company uniforms huddled or stood in packs talking and checking their phones. Some moving through the crowds were crying or visibly distraught.

Paul Vincent, a tourist visiting from England, was at a streetside bar when the quake struck.

“The next thing, everybody came on the street, so there was a lot of screaming and panicking, which obviously made it a lot worse,” he said.

As he came onto the street himself, he said he saw a high-rise building swaying and water was falling from a rooftop pool.

“When I saw the building, oh my God, that’s when ... it hit me,” he said. “There was people crying in the streets and, you know, the panic was horrendous really.”

Damage Reported in Nearby China
The earthquake was felt in Yunnan and Sichuan provinces in China and caused injuries and damage to houses in the city of Ruili on the border with northern Myanmar, according to Chinese media reports.

Videos that one outlet said it had received from a person in Ruili showed building debris littering a street and a person being wheeled on a stretcher toward an ambulance.

The shaking in Mangshi, a Chinese city about 100 kilometers (60 miles) northeast of Ruili, was so strong that people couldn’t stand, one resident told The Paper, an online media outlet.

Thai PM Promises All Necessary Help
Thai Prime Minister Paetongtarn Shinawatra said in a news conference that she has ordered relevant agencies to prepare and work to relieve the situation and warned of possible aftershocks. She didn’t mention any casualties.

“I’d like to ask everyone to stay calm and not panic, but please be careful.”

Bangkok City Hall has declared Bangkok an area of disaster.