People watch the 300-meter high SEG Plaza after it began to shake in Shenzhen in China's southern Guangdong province on May 18, 2021. Photo: AFP

One of China’s tallest skyscrapers was evacuated Tuesday after it began to shake, sending panicked shoppers scampering to safety in the southern city of Shenzhen.

The near 300-meter high SEG Plaza inexplicably began to shake at about 1pm, prompting an evacuation of people inside while pedestrians looked on open-mouthed from the streets outside.

The building was sealed shut at 2:40pm, according to local media reports. 

Completed in 2000, the tower is home to a major electronics market as well as various offices in the downtown of one of China’s fastest-growing cities.

Emergency management officials are investigating what caused the tower in Shenzhen’s Futian district to wobble, according to a post on the Twitter-like Weibo platform.

“After checking and analyzing the data of various earthquake monitoring stations across the city, there was no earthquake in Shenzhen today,” the statement said.

The district said in a later statement that everyone inside had been safely evacuated and that experts had found “no cracks in the ground surrounding the building and no pieces of outer wall had fallen or been damaged.”

It was not immediately clear how authorities will handle a dangerous tower of its scale in the heart of a city of more than 12 million people.

Bystander videos published by local media on Weibo showed the skyscraper shaking on its foundations as hundreds of terrified pedestrians ran away outside.

“SEG has been completely evacuated,” wrote one Weibo user in a caption to a video of hundreds of people milling about on a wide shopping street near the tower.

The building is named after the semiconductor and electronics manufacturer Shenzhen Electronics Group, whose offices are based in the complex.

It is the 18th tallest tower in Shenzhen, according to the Council on Tall Buildings and Urban Habitat skyscraper database.

Chinese authorities last year banned the construction of skyscrapers taller than 500 meters, adding to height restrictions already enforced in some cities such as Beijing.

The new guidelines for architects, urban planners and developers aimed to “highlight Chinese characteristics” and also banned tacky “copycat” buildings modeled after world landmarks.

Five of the world’s tallest skyscrapers are in China, including the world’s second-tallest building, the Shanghai Tower, which stands at 632 meters.

Shenzhen is a sprawling metropolis in southern China, close to Hong Kong, which has a booming homegrown tech manufacturing scene.

Many Chinese tech giants, including Tencent and Huawei, have chosen the city to host their headquarters. 

It is also home to the world’s fourth-tallest skyscraper, the 599-meter Ping An Finance Centre.

Building collapses are not rare in China, where lax building standards and breakneck urbanization lead to constructions being thrown up in haste.

Last May, a five-story quarantine hotel in the south-eastern city of Quanzhou collapsed due to shoddy construction, killing 29.

The devastating 2008 Sichuan earthquake caused more than 69,000 deaths and the disaster ignited a storm of public controversy over poorly constructed school buildings – dubbed ‘tofu dregs’ – which collapsed killing thousands of students.