Hybrid or electric-powered cars could be much more dangerous to pedestrians than traditional vehicles because of their silence, a report said Wednesday.

According to the report by Hyundai Marine & Fire Insurance Co., walkers are 1.6 times more likely to be run over by a quiet hybrid or electric car than by one with a gas or diesel engine outside schools, in residential areas and on other back roads.

The accident rate for slow-moving hybrids on back roads was 5.5 percent, compared to 3.5 percent for gasoline cars and diesel-powered vehicles, said the report based on an analysis of 234,000 car accidents involving the insurer's customers over the past two years.

Children and elderly people are more vulnerable to accidents, with comparable figures coming to 10.1 percent for kids aged 10 or under and 20.2 percent for people aged over 60.

The main reason for the high accident rate is the silence of green cars, which significantly impedes a pedestrian's ability to hear the approach of a vehicle when they travel at a low speed, it said.

"The main culprit is their quietness," the report said. "Quiet vehicles give drivers comfort but they can become a threat to pedestrians."

Experts said the government needs to take steps to protect pedestrians from silent vehicles.

"A law should be enacted to make noise generating systems compulsory on all hybrids when they travel at a low speed," said Lee Soo-il, a researcher at Hyundai Marine & Fire Insurance Co.

"That's all the more necessary because more people walk on back roads while talking on their smartphones."

The report comes as the number of eco-friendly cars on the road is rising fast in South Korea while the government offers tax breaks for green vehicles in an effort to help reduce air pollution.

According to government tally, green cars in the country numbered some 180,000 as of January, up 8.5 times from five years earlier. The number of registered vehicles in South Korea stood at 16.65 million units. (Yonhap)