A bus carrying people to a picnic area hit a land mine in central Afghanistan, killing 13 passengers and injuring six others, a U.N. official said Sunday.

The accident took place Saturday near Bamiyan, some 120 miles west of the capital, Kabul, said U.N. spokesman David Singh.

Passengers urged the driver to take a detour because of land mines on the main road, but he ignored their pleas, Singh said. A team later cleared the remaining mines from the road.

Singh said that of the six injured, one passenger was in serious condition. The bus was carrying 22 passengers, all Afghans en route to a picnic area near the eastern edge of Band-i-Amir lake, a picturesque resort area.

Two decades of war left an estimated 5 million to 10 million land mines littering Afghanistan, the vast majority of them left by the Soviets during their 10-year occupation.

The International Committee for the Red Cross estimates about 3,000 Afghans are maimed each year by land mines. According to U.N. estimates, 100,000 people have been injured or maimed over the past 23 years.

Despite months of intensive clearance efforts, land mines remain a deadly scourge for civilians and troops alike.

Children are the most common victims. But in March, a U.S. Navy SEAL was killed when he stepped on a land mine during a training mission near the U.S. base in Kandahar, Afghanistan's second largest city.