Government officials say 535 killed in Indonesia quakes

PADANG, Indonesia (CNN) - As many as 4,000 people could be buried under the rubble in the aftermath of the devastating earthquakes in Indonesia, United Nations officials said Saturday.

Local disaster management officials put the death toll from the quakes at 535.

Earlier U.N. figures that put the death toll at 1,100 were just estimates, said El-Mostafa Benlamlih, a U.N. humanitarian coordinator.

A 7.6-magnitude quake struck Sumatra on Wednesday and a 6.6-magnitude earthquake hit Thursday morning in the same region.

Wednesday's quake reduced buildings to rubble in the city. People used hammers, chisels and bare hands to dig through debris for survivors and belongings.

Staff at a local hospital treated the injured outside the semi-collapsed building as bodies of the dead lay in makeshift morgues.