Of the animals, 106 had died of asphyxiation upon discovered.

The surviving animals were all culled Saturday at a local veterinary station since they failed to satisfy prescribed hygiene standards.

Nguyen Quoc Tuan, 32, was driving a bus towards the north when he reached a Covid-19 checkpoint near National Highway 1A on Friday afternoon. Authorities here soon detected the sound of dogs and cats coming from the vehicle.

Upon being questioned, Tuan failed to provide documents stating the origin and destination of the bus, while not allowing passengers off to have their body temperatures checked and declare themselves medically.

"The bus was not approved to carry animals, and the driver might face a heavy fine for opposing traffic police," said Doan Ngoc Minh Tuan, deputy head of the Da Nang traffic police department, adding the origin of both the dogs and cats remained unknown.

A traffic police officer got trapped onboard the bus following a commotion.

Authorities eventually managed to subdue the driver, transferring the 37 passengers north for free.

Driver Tuan is currently under investigation for opposing authorities at a Covid-19 checkpoint.

Dog and cat meat consumption is common in Vietnam. The trade is not illegal, but stealing dogs and cats worth more than VND2 million faces criminal charges.