A police official said they suspect that negligence on part of the van's driver led to the mishap near Gadwal town, located about 175 kms from here.
"More than 30 labourers working in a ginning mill were travelling in the vehicle when the accident took place. Five of them died on the spot and 30 people were injured," the official said.
The injured, including the van's driver who sustained multiple fractures, were admitted to different hospitals, he said.