BEIJING, Sep 16 (AFP) - Two people were killed and dozens injured when a shallow earthquake struck south-western China in the early hours of Thursday (Sep 16), triggering the second-highest level of emergency response by rescuers in Sichuan province.

The US Geological Survey put the magnitude of the quake at 5.4 but the China Earthquake Networks Centre measured it at magnitude 6.0. Both put it at a shallow depth of 10km.

It struck Luxian county around 120km south-west of the sprawling megacity of Chongqing, which along with its surrounding area is home to around 30 million people.

Luxian authorities said the seismic event had left "two dead, three seriously injured and 50 slightly injured, while 22 houses in the county collapsed".

Scores of houses have been damaged, while communications had been disrupted to tens of thousands of people.

But authorities downplayed the immediate threat of a larger aftershock.

"It is unlikely there will be a larger earthquake in the area in the near future, but aftershocks will continue for some time," Du Bin, deputy chief of the Sichuan Earthquake Administration, told reporters.

State broadcaster CGTN confirmed the death toll, sharing security camera footage showing TVs and refrigerators shaking on the walls of houses as the quake struck, as ornaments smashed onto floors and cracks ran through buildings.

Bricks were strewn across roads and trees felled in some areas as firefighters clawed through the rubble of collapsed houses, the images showed.

Residents were urged to stay outside of their homes, state media reported, although images showed there was little sense of wider panic by residents in an area of high seismic activity.

The USGS said that "significant damage is likely and the disaster is potentially widespread", in a preliminary assessment.

The Sichuan government said in a Weibo statement that multiple power lines had been disrupted and 62,000 households were hit by power cuts after the earthquake.

A powerful 7.9-magnitude quake in Sichuan province in 2008 left 87,000 people dead or missing.

Among them were thousands of children, killed when poorly constructed school buildings collapsed, but the government failed to release an exact number of dead as the issue took on a political dimension.

Police detained activists who attempted to count the number of children who had died and mark the buildings that collapsed amid suspicions of poor construction.