Bina Darma University student Bedrirta Sepriana and her group of friends were looking for a musholla, or place to pray, in the Indonesia Stock Exchange (IDX) building on Monday when the walkway they were on gave way, sending them crashing one floor down.
"There was no warning - I was near the edge at the railing, using my phone to take a photo, when it suddenly collapsed and I fell 7m or 8m down. I was also crushed by my friend's body," said the accountancy undergraduate.
When Ms Bedrirta looked around, she saw her friends lying on the ground floor with blood splattered over broken glass and other debris.
"I thought it was an earthquake and I was afraid there would be another quake, so I quickly crawled out and found a security guard and an IDX staff member who helped me out," the 21-year-old told The Straits Times yesterday.
Ms Diana Febrianti, who is also from the university, said she heard a loud creaking sound before the walkway on the mezzanine floor collapsed.
"I was the last person to fall, and when I tried to get up, I cut my hands on the glass fragments on the ground," she said. "There was also a lot of blood flowing from the right side of my face."
Amid the chaos, the 19-year-old managed to find IDX president director Tito Sulistio, who was with her group. "He immediately carried me out of the building and got some people to flag down a taxi, which took me to the hospital on my own," added Ms Diana. "In the taxi, I contacted my parents."
The two young women are warded at Siloam Hospital, where 28 victims from the incident are recovering. Most of the 77 people hurt were from Bina Darma University in Palembang, South Sumatra. They were in Jakarta on a study trip, and the IDX was their first stop since their arrival in the capital on Sunday.
Jakarta police spokesman Argo Yuwono said yesterday that 61 people remained in hospitals.
The usual hustle and bustle at the IDX building was absent yesterday morning.
Tower 2, where the incident occurred just before lunchtime on Monday, was blocked off, with only selected representatives of tenants allowed in. Those who turned up for work at Tower 2 were told they could not enter the building until further notice, although access to Tower 1 was possible.
Ms Farida Riyadi, a director of Cushman & Wakefield, which manages the IDX building, told reporters yesterday evening that work to clear the affected area would be completed, and Tower 2 would be reopened today.
She added that the collapse of the walkway was due to the failure of a secondary structure, and the main building remained safe.
She declined to pinpoint the exact cause of the collapse, but said the load on the walkway may have exceeded the capacity of the suspension rods that held it up.
Local media, quoting a leaked document, reported that a preliminary study by officials also blamed overloading for the collapse, prompting the Public Works and Housing Ministry to clarify that it was an unofficial, preliminary report based on an internal study by its staff.
The IDX building is now under audit by the Jakarta provincial government, while the police and other authorities continue investigating Monday's incident.