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

“All of a sudden, the whole building began to move. Immediately, there was screaming and a lot of panic,” he said. Some people fled down upward-moving escalators, 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.”

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

Many were on phones trying to reach loved ones as others sought shade from the hot early afternoon sun. Others stared up fearfully at the tall buildings in the densely packed part of the city.

“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.”

The sound of sirens echoed throughout central Bangkok and vehicles filled the street, leaving some of the city’s already congested streets gridlocked. The elevated rapid transit system and subway were shut down.

City hall declared the city a disaster area to facilitate interagency aid and emergency help.

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.”

The U.S. Geological Survey and Germany’s GFZ center for geosciences said the midday temblor was a shallow 10 kilometers (6.2 miles), with an epicenter in neighboring Myanmar, according to preliminary reports.

The greater Bangkok area is home to more than 17 million people, many of whom live in high-rise apartments.

Alarms went off in buildings as the earthquake hit around 1:30 p.m., and startled residents were evacuated down staircases of high-rise condominiums and hotels in densely populated central Bangkok.

Thailand’s Department of Disaster Prevention said the quake was felt in almost all regions of the country.

Tremors rattled high-rise buildings across Bangkok, swaying towers, cracking walls, and causing water to slosh out of rooftop swimming pools. Videos circulating online showed a crane-topped building crumbling into a cloud of dust while onlookers screamed in panic.

So far the earthquake has killed over 150 in Myanmar, Thailand.