More than a dozen Muslim students at an Islamic school in Nigeria’s central Plateau State were killed or injured when the two-story building buckled Sunday. About 40 pupils of various ages were attending classes at Abu Naima Primary and Secondary School in the town of Bukuru at the time of the collapse, which killed at least four students and injured 14 others, according to Reuters.

"We are still working under the rubble for more bodies and injured," Abdulsalam Muhammed, the state coordinator for Nigeria’s National Emergency Management Agency, reportedly said Sunday.

Muhammed said many of those who survived the collapse sustained severe injuries and were transported to a nearby hospital in Plateau State. The death toll was expected to rise as rescue efforts continued, Nigerian newspaper Premium Times reports.

Parents of students hurried to the scene, and some were unsure if their children were alive or dead as rescuers searched for more bodies and survivors beneath the ruins. One parent said the school was poorly constructed, and believed that heavy rain had contributed to its collapse.

"We rushed here to find out if our children are alive," father Ahmed Abubakar told Reuters Sunday. "We only hope Jamila, my daughter, and Saleh are not among the dead."