Search teams are finding more bodies than survivors in the rubble
A strong earthquake hit Peru on Friday, striking panic into local people and rescuers still searching for survivors of Wednesday's devastating quake.
It is not known whether the aftershock, which the US Geological Survey website listed at a 5.9 magnitude, caused further damage or loss of life.
At least 500 people were killed when Wednesday's quake wrecked parts of Peru's central coast, officials say.
The hunt for survivors goes on, and dead bodies are still being retrieved.
Friday's aftershock, which struck at about 0820 (1320 local time) was one of some 300 that have followed Wednesday's quake, the Peruvian Geophysical Institute said - and one of the strongest.
The worst damage from the main earthquake was in the coastal cities of Ica and Pisco, south of Lima.
Tens of thousands of people have lost their homes, while power supplies, telecommunications and road links have been severely disrupted.
Hospitals and mortuaries have been overwhelmed, and the bodies of many victims that have been recovered from the rubble are lying on the streets.
The head of the Peruvian fire service, Roberto Ocno, told AFP news agency: "The toll has jumped to between 500 and 510 dead and 1,600 injured. There are dead trapped under houses."
In Pisco, firefighters, police officers, soldiers and volunteers worked through Thursday night under floodlights to dig through the ruins of the church in the main square.
Hundreds of people were buried when the building collapsed during a Mass, but the discovery of the male survivor lifted the rescuers.
"This is virtually a miracle - hopefully we can find more," said Carlos Cordova Gomez, chief of Peru's voluntary firefighters.
But, as dusk fell, Health Minister Carlos Vallejos said hopes were dwindling.
"We keep losing hope of finding someone alive after 24 hours have passed," he told the Associated Press news agency.
The BBC's Luis del Valle, in Pisco, says people are in shock and local civil defence officials have acknowledged they have been overwhelmed by the scale of the disaster.
A local Oxfam spokesman, Renato Guinaraes, said getting relief supplies to those who needed them was a huge challenge.
"There is a problem with a lack of shelter. People are suffering because of the cold weather, lack of potable water and general conditions of living," he told the BBC.
"The overall infrastructure of the cities was totally destroyed, not only the hospital but most of the cities are simply destroyed."
The authorities are still trying to reach remote villages and hamlets in the region, from where there has so far been no news.
The government said helicopters and planes were taking emergency aid to affected areas, and injured people are being airlifted out.
President Alan Garcia has visited the region and sent condolences to the families of the victims. Three days of national mourning have been declared.
An international humanitarian relief effort has been mobilised.
Other countries in the region - including Ecuador, Bolivia, Brazil, Mexico, Venezuela, Colombia and Chile - have sent relief supplies.
Help is also coming from the United States, Canada, Spain, Italy and France.
The United Nations said it was ready to help, while the International Federation of the Red Cross said it had sent two planes loaded with supplies. The latter also launched an appeal for emergency aid.
The earthquake happened in one of the most seismically active regions of the world.
In 1970, a 7.9-magnitude earthquake high in the Peruvian Andes triggered a landslide that buried the town of Yungay and killed 66,000 people.
EARTHQUAKE DISASTER ZONE, AND TECTONIC PLATES
Earthquake struck on Wednesday at 1841 local time
The 8.0-magnitude earthquake was centred just off the coast of Peru
Two tectonic plates clash at this region, the Nazca plate and the South American plate
There is about 7-8cm (3in) movement between the plates a year
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