An earthquake measuring 5,2 on the Richter scale shook southern Brazil overnight, scaring many but causing no significant damage or casualties, officials and media said.

It was the strongest temblor to hit the region in a century, the news group Globo said.

The epicentre was 270km off Brazil's south-east coast, the Seismological Observatory of Brasilia University said.

The unit's coordinator, Jorge Sand, said the zone has a history of seismic activity because it is on the edge of a continental plate.

The city of Sรฃo Paulo felt the movement the most, with residents in high-rise apartments feeling their buildings sway. Rio de Janeiro was also affected.

Several inhabitants in some parts were seen going into the street in their pyjamas, with a few stringing up hammocks to sleep outside for fear of further tectonic shocks.

Fire services said they had received more than 400 calls from startled citizens.