Chinese television read an urgent notice to the public today not to believe rumours of aftershocks from the earthquake that has killed as many as 70,000 people, in a bid to prevent panic taking hold.

The six-point notice was broadcast by newsreaders on Sichuan Television, after a warning last night of strong aftershocks sent terrified residents rushing from their homes of Chengdu, capital of the province devastated by last week’s massive tremor.

A statement on the provincial government's website said: "There is a heightened possibility of an aftershock of between 6.0 and 7.0 magnitude on May 19 and 20 in the region of the Wenchuan 8.0 magnitude quake."

A 5.0-magnitude quake rattled Pingwu county, about 125 kilometres (77 miles) north of Wenchuan county, the epicentre of last week's earthquake. The aftershock at 1:52 a.m. (1852 GMT) jolted Chengdu residents.

Thousands of residents poured onto the streets of areas near the epicentre and in Chengdu, the provincial capital. Large crowds camped out overnight as far away as Chongqing, 270 kilometres (167 miles) from Chengdu. Chengdu residents carried bedding, chairs, clothes and other possessions as they left their homes seeking the safety of open ground.

Giant traffic jams developed as drivers headed toward the suburbs or open spaces such as parks, construction sites and stadiums. It was almost impossible to use mobile telephones as frightened residents deluged the system with calls to relatives.

A middle-aged couple strolling along the riverside said they had deposited their elderly parents in a public bus made available as a place for residents to sleep if they were too afraid to go home. The husband said: “There’s no room for us. So we are just going for a walk. We’ll see later where to sleep.”

On one Chengdu street, a huge line snaked out of a store selling camping gear this morning. Chengdu resident Cheng Wenjun said: “I slept in my car and my family slept in a tent. Those who had tents slept in them and those with cars slept in them."

The notice from the Seismological Bureau said only county-level government departments were allowed to issue warnings of aftershocks and warned people to ignore any other notices as pure rumour.

It said: “Any 'prediction' of an earthquake at a certain time and in a certain place is certainly a rumour. Because currently in the world the level of earthquake prediction is impossible to achieve this kind of accuracy.”

One earthquake expert's reassurances were broadcast repeatedly today on Sichuan television. He said: "The great Wenchuan earthquake did not cause damage in Chengdu. The difference between magnitude 8.0 and mangnitude 7.0 is 30 times. Since no damage was caused in Chengdu by that earthquake, then nothing is likely to happen from this."

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