ANKARA

At least 91 students are believed to be trapped under the rubble of a boarding school building that collapsed in Indonesia's East Java province, officials said on Wednesday.

The National Agency for Disaster Management (BNPB) revised its earlier estimate of 38 missing people, saying student attendance records showed 91 people are still buried beneath debris as of Wednesday morning.

The collapse occurred when the foundation pillars gave way under the added weight of a newly built fourth floor, BNPB spokesperson Abdul Muhari said.

A combined search and rescue (SAR) force of 332 personnel has been deployed, including teams from local disaster agencies, police, and military officials, according to a BNPB statement.

Heavy machinery remains on standby but cannot yet be used due to fears that vibrations could cause further collapse.

On Tuesday, the National Disaster Mitigation Agency said the incident occurred at Al Khoziny Islamic Boarding School while hundreds of students were gathered for prayers. A total of 102 people were rescued, while three others were confirmed dead following the collapse.

While 77 people were taken to hospitals, 26 are still receiving treatment, while the rest have been discharged.