Residents look at a collapsed building in Concepcion, Chile’s second largest city, which was 115km from the epicentre of the original quake.
A 6.7-magnitude aftershock has struck off Chile's coast some 72 kilometres from Concepcion, among the cities hardest hit by last month's 8.8-magnitude quake, US seismologists said.
The US Geological Survey said the quake hit at a depth of 35 kilometres on Monday night local time, but no tsunami watch was issued.
"No destructive widespread tsunami threat exists based on historical earthquake and tsunami data," the monitoring office said.
"However, earthquakes of this size sometimes generate local tsunamis that can be destructive," it added.
A tsunami that followed the massive February 27 quake in Chile wiped out entire coastal villages.
Questions over why a tsunami warning was not issued more quickly after that temblor led to the firing of the head of Chile's navy Oceanography Service.
The latest aftershock was one of more than 200 to rock the South American nation since the February quake.
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