The students who died were between 5 to 10 years, rescue operations took 3 hours. (Representational)

Four students died when the roof of a school toilet collapsed in Nepal's Darchula district on Tuesday, authorities said today.

The incident took place when the roof of the toilet at the Ganesh Secondary School collapsed in Naugadh rural municipality of the district, some 500 km west of the capital city Kathmandu, reported Xinhua news agency.

"We have recovered four bodies of children from the incident site," a police officer said.

The students who died were between five years with 10 years old, the official said.

It took at least three hours to conduct the rescue operations, the official added.