The leak was initially noticed on the first floor of a residential building in the city's Xigang District.

A man surnamed Chen saw his two dogs foaming at the mouth when he got up at 6 am.

He immediately called his veterinarian, who happens to live nearby, and the vet concluded that the dogs were suffering the effects of poisonous gas.

Police and medics rushed to the scene when Chen reported a possible gas leak.

Five people were found dead on the spot and more than 40 people, including Chen's wife, were treated by ambulance crews.

All the injured were taken to six local hospitals. Local sources said another two seriously poisoned people died later.

The poison was not only in Chen's building but had spread to another five neighboring residential blocks, covering 144 households overall.

Rescue workers evacuated 424 people from near the site of the gas leak.

A preliminary investigation located the leak on the building's cooking gas pipeline.

The damage was caused during recent repair work to a heating pipe, Sun Jichu, a senior official of the Dalian municipal government, was quoted as saying by China News Services.

Emergency repairs were being carried out yesterday on the gas pipeline and the gas supply was expected to return to normal soon, said the city government.

The Dalian accident followed last Thursday's gas explosion in a residential building in Changchun, capital of Northeast China's Jilin Province. Three people died and 14 were injured in that accident.

(China Daily December 16, 2002)