Workers cover a window to block the view inside a building at the Indonesia Stock Exchange following reports of a collapsed structure inside the building in Jakarta, Indonesia January 15, 2018. Photo: Reuters/Darren Whiteside

The mezzanine floor overlooking the main lobby of the Indonesia Stock Exchange (IDX) building collapsed around noon on Monday, injuring around 20 people, according to media reports.

The building is part of a two-tower complex which was the target of a suicide bombing by Islamist militants in September 2000, but police ruled out a bomb or terrorism as the cause of Monday’s collapse, Reuters reported.

IDX president director Tito Sulistio said fewer than 20 people were injured. There were no reported deaths. An official IDX statement on the collapse did not mention a cause for the accident, the Jakarta Globe reported.

Footage aired on local television MetroTV and circulated on social media showed several people lying on the ground at the entrance of the building near a Starbucks coffee shop, the local Jakarta Post reported.

Police cordoned off the complex as people fled the building, as the injured, including students visiting the building, were taken away by stretcher, according to agency reports.

“The second floor of the building has collapsed,” said Vindy, a personal assistant to the exchange’s president director, Tito Sulistio, who was in the building at the time, Reuters reported.

“Slabs of concrete started to fall, there was lots of dust. Water pipes had burst,” said Megha Kapoor, who works in the building and was in the lobby at the time.

“I heard a loud cracking sound. I saw a lady unconscious stuck under slab of concrete,” she said, adding that the collapsed level was just above the reception desk. She said a group of high school students was on the level when it started to collapse.

Despite the morning collapse, the benchmark index was little changed  before the lunch break. The local bourse resumed business as usual in the afternoon, reports said.

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