Early on Wednesday morning, Hangzhou citizens in eastern China were alarmed to discover a large hole on the surface near the northern end of the "Broken Bridge" of its West Lake. The roadbed has sunk during the night.

"It must be the result of a heavy derrick car operating here during the night. This is illegal!" the sentry of the bridge said angrily. "I was still on duty at 10 o'clock last night. The daredevil must have sneaked in to work here at midnight!"

There are sign boards forbidding parking or passing on the bridge at both ends of the bridge. Obviously the driver of the derrick car turned a blind eye to them.

On Thursday morning, the surface layer roadbed of the Broken Bridge had to be dug up for the road maintenance team to do rush repairs to prevent further damage to the ancient bridge. Under the pitch layer, two-meter-long stone slabs were sunken, while the rammed earth foundation were crushed. Rescuers reinforced the roadbed by pouring in concrete. The bridge hasn't undergone "surgery" on such a scale for almost 50 years.

West Lake has no wharf, so large touring boats have to be first lifted up by crane and then put into water. The bank near the northern end of the Broken Bridge is spacious, so most of such lifting works are done there.

All lifting work must first be authorized by the administration office of the scenic area and calculations done beforehand to make sure the lifts will do no harm to the Broken Bridge. The incident on Tuesday night is an obvious illegal case.

According to historic records, the Broken Bridge was in existence as early as the Tang Dynasty. The current bridge was rebuilt in 1941 and repaired in the 1950s. Since then, no large-scale construction has taken place on it.

The administration office is now tracing the lawless derrick vehicle and expressed hope that citizens and tourists in Hangzhou who love the precious ancient bridge will never park cars on it.

Broken Bridge is a famous attraction on West Lake, Hangzhou. Its name is derived from history, when winter snow melted first from the center of the bridge, causing it to look like a broken bridge from a distance.