Two commuter buses collided in the Gaeseong Industrial Park in North Korea last week, killing 10 North Korean workers. About 40 others were injured.
The accident, which occurred last Friday, was made public later by a South Korean worker who commutes from South Korea to the industrial complex, according to Paju police.
No South Korean workers were hurt as the vehicles carried only North Koreans.
"We were told that bad weather conditions was the probable cause of the incident. But we do not know the exact cause and the exact number of casualties," said a police officer who asked not to be named.
About 40,000 North Korean workers use the buses to commute to their workplaces at the site.