At least two people were hospitalised with serious injuries after the incident in the town of Novi Sad.
At least eight people have been killed after a concrete roof above the entrance of a railway station in the northern Serbian city of Novi Sad collapsed.
At least two other people were hospitalised with serious injuries on Friday, Serbian Interior Minister Ivica Dacic said.
The minister said rescuers were in contact with two people who were still trapped beneath the rubble.
“The operation is still ongoing and extremely challenging. Over 80 rescuers are involved, with the assistance of heavy machinery,” he added.
Ambulances and other emergency teams were dispatched to the downtown station and bulldozers were removing the debris looking for survivors.
Surveillance camera footage showed people moving in and out of the building and sitting on benches on a bright, sunny day before the concrete canopy suddenly collapsed on them.
The station, in Serbia’s second-largest city, reopened in July after three years of renovation work. Construction work was continuing in parts of the station.
Dacic said the rescue operation was “extremely hard” and that it would last for at least several more hours.
The Blood Transfusion Institute in Novi Sad called on residents to donate blood following the accident.
Serbia’s Prime Minister Milos Vucevic promised that authorities would investigate the cause of the accident.
“We will insist on finding those responsible, those who should have ensured the structure’s safety. My condolences to the families of the deceased,” said the prime minister.
“This is a black Friday for us, for all of Serbia, for Novi Sad,” he added.
Serbia Railways said in a statement that the outdoor roof that collapsed had not been part of the renovations completed at the station. It said the accident happened at 11:50am local time (10:50 GMT).
“Serbia Railways regrets the accident that occurred, and the causes and any new details from the investigation will be promptly announced,” the company wrote in a social media post.
Local media said potentially dozens of people were injured. The mayor’s office in the city acknowledged the incident but did not say how many were hurt.
N1 news channel said that train departures were halted from the station about 70km (43 miles) northwest of the capital Belgrade.
