Indonesian rescue workers 'racing against time' in search for dozens in rubble of collapsed school

Most rescues typically happen within 24 hours after such a disaster, with chances of survival decreasing each day after that, and more than 300 workers continued to work desperately at the scene to try and reach those who have been detected to be still alive and trapped below.

“We hope that we can complete this operation soon," Mohammad Syafii, head of Indonesia’s National Search and Rescue Agency, told reporters.

"We are currently racing against time because it is possible that we can still save lives of those we have detected within the golden hours,” he said at the news conference.

Of the approximately 100 injured, 26 are still hospitalized and many are said to have suffered head injuries and broken bones, authorities said.

Syafii's agency said at least six children are alive under the rubble, but the search has been complicated with the slabs of concrete and other parts of the building remaining unstable. Heavy equipment is available but is not currently being used due to concerns it could cause further collapse.

Rescuers have been running oxygen, water and food from narrow gaps to those still trapped under the debris to keep them alive.

Search teams have also used detectors and thermal drones to detect potential survivors who could be rescued.

The structure fell on top of hundreds of people at about 2:30 p.m. on Monday in a prayer hall at the century-old al Khoziny Islamic boarding school in Sidoarjo, on the eastern side of Indonesia's Java island.

The students were mostly boys in grades seven to 12, between ages 12 and 18. Female students were praying in another part of the building and managed to escape, survivors said.

The prayer hall was two stories high but two more were being added without a permit, according to authorities. Police said the old building’s foundation was apparently unable to support two floors of concrete and collapsed during the pouring process.

Authorities initially had said only 38 people were missing but revised that upward to 91 late Tuesday after consulting attendance lists and talking with families.

“In the early stages there will inevitably be some confusion about the data,” said Suharyanto, the head of the National Disaster Mitigation Agency, who only goes by one name as is common in Indonesia.

Tarigan reported from Jakarta, Indonesia. Associated Press writer Niniek Karmini in Jakarta contributed to this report.