Brian Barron: "There is no hope that any are still alive under the rubble"

Mobs of residents, angry at the slow pace of relief efforts and driven by hunger, broke into stores in Armenia to cart off armfuls of powdered milk, bottled water and canned foods.

Riot police backed by army troops fired bursts of automatic gunfire into the air but were largely unable to quell the frenzy.

The chaos came as the Red Cross confirmed the death toll from Monday's quake had climbed to 878 with more than 3,400 people injured.

But those numbers are expected to rise as the debris is cleared. One official in Armenia predicted the final death toll there would reach 2,000.

Rescue teams have arrived from Britain and the United States, but hope of finding new survivors is dwindling fast.

'It isn't stealing'

At least six civilians were injured in Wednesday's disturbances as people threw rocks at riot police.

One looter said: "It isn't stealing. The store's totally destroyed, and nobody has a house, nobody has food. All this is to share with the people."

Several officials said they were reluctant to crack down on people who had spent more than 48 hours without food or drink.

"What can I do if people are dying of hunger?" asked one policeman.

$3m in disaster relief

The quake, measuring 6.0 on the Richter scale, created a disaster zone that covered 20 towns and villages in five provinces in Colombia's central coffee-region. Landslides triggered by the quake's eight aftershocks also cut off many areas.

James Reynolds reports: There is considerable confusion as to who survived and who was killed

Government convoys arrived at disaster scenes with cranes and other heavy equipment, and an air force plane shuttled medical supplies, food and blankets to the region.

The US pledged $2m in disaster relief while the Colombian president's office said the European Commission had promised $1.1m.

Hopes of finding survivors are fading fast

First Lady Nohora Pastrana went on television to appeal for patience, promising Colombians relief was on the way.

"We are sending tents, food, help for the children ... International groups are coming, too, to help us remove the rubble," she said. "Have patience, because we are doing everything humanly possible to tend to everyone's needs."

The Health Ministry has declared an official emergency. There are appeals for blood donors for the living and coffins and refrigerated trucks to store the dead. Doctors from across the region have also been called in.

'Complete catastrophe'

Scientists said the quake was less than 20 miles (32 km) below the surface - far less than normal - with the epicentre located in a mountainous region 115 miles (185 km) south-west of Bogota.

Rolin Wavre of the Red Cross in Colombia: "The people need medical aid, food and shelter"

Henry Gonzalez, government secretary in Armenia, said the city had not been prepared for a disaster of this magnitude.

Authorities in Armenia say half the buildings have been destroyed or severely damaged. Fires broke out on Tuesday night and many people fled the city to sleep in the open.

Officials say that the area's coffee crop, which counts for half of what Colombia exports, is not affected but the price of beans has already risen sharply on the London market.