Five day laborers, including three Chinese nationals, were killed in a traffic accident in Ansan on Saturday while heading to a worksite, local authorities said.

The accident occurred in Ansan, about 30 kilometers south of Seoul, at around 5:45 a.m., while the victims were heading to a worksite in a van, according to Gyeonggi Province fire services.

The van carrying the victims collided with a bus and hit a passenger car before coming to a stop, resulting in a total of 14 casualties.

The five laborers in the van were sent to a nearby hospital shortly after the accident but were pronounced dead, while nine people, including the driver and other passengers in the van, were injured.

Among the injured, one is reportedly in critical condition.

Police said none of the drivers of the vehicles involved were under the influence of alcohol, adding that an investigation into the exact cause of the accident is being conducted.

The police suspect the van caused the accident by violating a traffic signal.