By Andrei Lankov

In wartime Seoul, one of the most prominent sights was that of the Han River bridges: half-destroyed, with arches protruding from the shallow waters of the river.

One expects that the troops of a retreating army would demolish the bridges behind them, and that was just what the Southerners did.

However, the demolition was done in a way which inflicted far more harm on the South Korean forces than on their North Korean enemy.

The Korean War broke out in the early morning of June 25, 1950, when North Korean forces began a speedy advance across the border. According to a battle plan drawn up by their Soviet advisers, the North Korean generals concentrated all their forces against Seoul and pressed hard.

The South Korean defenses crumbled, and the ROK troops began a disorderly retreat. A majority of Seoulites did not care much, since many people were deeply apolitical they did not expect to see a great deal of difference between the governments of the South and the North, but some people in the city had good reason to be afraid of the advancing communists.

Government officials, clerks from the U.S. offices, policemen and religious activists would not be treated nicely in a Communist-controlled Seoul, and they knew it.

When the advancing sounds of the Reds' artillery made it clear that the city was doomed, they rushed to the Han River bridges which provided the only escape route from Seoul.

In 1950, three bridges (one for railroad traffic) connected Seoul with the southern bank of the river. At that time all of Seoul was located on the northern bank, so the cross-river traffic was normally small.

But by the morning of June 27 the narrow bridges were crowded with people, both civilians and soldiers from retreating South Korean units.

Around midday the bridges were closed to civilian traffic, but some people managed to get through, and there were organized groups of civilian refugees as well.

On the morning of June 27, Colonel Choe Chang-sik was ordered to place high explosive charges and to be ready to demolish the bridges when it was be deemed necessary. It was clear that Seoul would be surrendered soon, but the military command tentatively decided that the Han River bridges would be demolished on the morning of June 28.

With the wisdom of hindsight we know that this was good timing, since the North Korean units had begun to infiltrate downtown Seoul at that time. However, it did not work out as intended.

At 2:30 a.m. a terrible explosion wiped out a few sections of each bridge. The charges were detonated even if the bridges were still crowded with soldiers and refugees. Nobody attempted to stop them or clear the bridges.

It is not known why Colonel Choe gave the order. Obviously, he followed an instruction from above, perhaps from the then head of staff General Chae Pyong-dok, but this has never been proven beyond doubt.

According to one theory, there were unsubstantiated reports of North Korean tanks being seen in the vicinity of the bridges, and this prompted the order, by General Chae or somebody else.

Whatever the reason, the bridges were blown up with all people who were rushing south on them. The true scale of the disaster will probably remain unknown forever. It is believed that between 300 and 800 people, both military and civilians, were victims of the explosion.

Most of them were killed or drowned in minutes. Cries of the wounded and dying were heard far away. People asked for help, but in the darkness and confusion there was little chance of saving anyone ― and nobody tried. The officer who actually detonated the charges, Major Om Hong-sop, was seen walking in tears amidst the destruction he had to unleash.

In the long run, there were many more victims. The explosion cut off a large part of the South Korean army: three infantry divisions were stuck on the northern bank of the Han River, badly outnumbered by the enemy.

Many soldiers eventually escaped, swimming across the river or using what available boats there were, but thousands were taken prisoner. Many of them eventually died in captivity or were shot. All heavy weapons had to be left behind, so the strength of the South Korean army was severely undermined.

The North Koreans tried to restore the bridges, but their attempts were in vain. The U.S. air force had unchallenged command of the air, so every time construction was complete a U.S. air raid wiped out the bridges, and the North Korean engineers had to start their work anew.

Such a disaster needed a scapegoat, so Colonel Choe was arrested soon afterwards.

He had no way to prove that he had acted on the instruction from his superiors, so in September 1950, when the military fortunes of the South had reached their nadir, the colonel was condemned to death and shot ― much to the outrage of his fellow officers who saw this as a typical case of scapegoating by corrupt and incompetent politicians.

It took 14 years before Colonel Choe's case was re-considered, and then he was posthumously acquitted. This acquittal took place in December 1962 when the country was under military rule.

Colonel Choe's widow said when she learned about the decision: ``It's great. But no one can say sorry to all those people who did not cross the Han River.''

Prof. Andrei Lankov was born in St. Petersburg, Russia, and now teaches at Kookmin University in Seoul. He has recently published ``The Dawn of Modern Korea," which is now on sale at Kyobo Book Center and other major bookstores. The book is based on columns published in The Korea Times. He can be reached at anlankov@yahoo.com.