Water and gas pipes under Guomao Bridge in Beijing's Central Business District (CBD) burst early Monday, causing huge traffic jams on the East Third Ring Road, with 15 bus routes diverted and water and gas cut off in nearby buildings.

The incident took place at 2:30 Monday morning, when a worker was drilling on a site on a side road and accidentally burst a 60 cm water pipe.

Staff from Beijing Waterworks Group shut a water valve, but a two sq m hole was left on the road due to the significant pressure of the water pipe.

Firefighters also found that a gas pipe had burst and police immediately cordoned off the area.

"It was very dangerous. Even

a tiny spark might ignite the gas," one firefighter was reported as saying.

A security guard surnamed Wang told METRO that at 7 am the side road where the incident took place was filled with water and mud and had been closed-off by police.

He said heavy machinery was being used to dig holes in the road to expose the pipes and that 30 to 40 workers in the uniforms of Beijing Waterworks Group and Beijing Gas Group were busy repairing the cracked pipes.

The odor of the gas leak made passersby cover their noses.

"The smell was really bad. It made me nauseous," Wang said.

The odor of the gas didn't fade away until around 11 am.

The incident made Beijing's already notoriously bad Monday morning traffic even worse.

Beijing traffic management bureau dispatched 600 more traffic police to the CBD and surrounding areas to direct traffic.

However, according to Wang it wasn't very effective.

"I didn't see any cars moving for more than five minutes during rush hour," said Wang.

The work to stem the damage was a big project. Workers had to drain water from the area before repairing the pipes.

The company held responsible for the incident was not confirmed.

No casualties or injuries were reported.

More than 500 households and office buildings were affected as water and gas to buildings on the east side of Guomao Bridge were cut off.

When Peng Zhihuai, who lives across the road from the site, woke up on Monday morning, he had

no water to drink and the gas was not stable enough to make breakfast.

"I called the property management company and learned water and gas was shut off around 3 am on Monday and there was no further notice on when it was coming back," he said.

The pipes were repaired by 5 pm and traffic restrictions were lifted.