Traffic in east Beijing was disrupted Monday when two underground piplines carrying water and gas under Beijing's Guomao Bridge were broken during roadworks.

A witness said the accident happened at around 2 a.m., in the northwest corner of Guomao Bridge, on the east section of Beijing's Third Ring Road.

The witness said a strong smell of gas filled the air and police came immediately.

Police cordoned off the scene. Workers are repairing the pipelines.

The north-west ramp on the Guomao Bridge and the north-south slip road from the intersection of Guanghua Road and the Third Ring Road to the Guomao Bridge were closed temporarily.

Meanwhile 15 bus services were rerouted to avoid the site.

More than 600 traffic police have been mobilized to help ease the traffic. Fire fighters are also standing by.

No casualties have been reported.

Traffic was resumed at around 10:28 a.m..

Gaomao is near the Beijing central business district, site of the Chinese World Trade Center.