Chile was jolted by a magnitude 6.7 aftershock that struck off the coast of the South American nation Monday night about 45 miles (72 kilometers) northwest of Concepcion, one of the hardest hit by late last month's 8.8-magnitude quake.
The ground shook violently for 30 to 60 seconds forcing panicky residents to rush out of buildings for safety.
The US Geological Survey (USGS) said the epicenter of the aftershock was located 21.7 miles (34 kilometers) deep in the Pacific Ocean. The national emergency office, known by its acronym ONEMI, said no casualties or damage to infrastructure had been reported nor any tsunami alert issued.
"The characteristics of this quake do not merit a tsunami (alert). The situation is normal," said Vicente Nunez, head of ONEMI adding that there were no reports of casualties or damage to infrastructure.
The Pacific Tsunami Warning Center said historical data indicated the aftershock would not generate a tsunami but still advised authorities in much of the Pacific region to be wary of the possibility.
The devastating magnitude 8.8 tremor and ensuing tsunamis on February 27 killed about 500 people and ripped up roads and towns besides wiping out the entire coastal villages. It caused an estimated $30 billion in damage to infrastructure, homes and industry.
The strong aftershock came a day after Chile experienced a massive power outage following the failure of a key transformer on Sunday night that stretched 1,250 miles (2,000 kilometers) and affected up to 90 per cent of the population.
On Sunday at 9:40 p.m. local time (2440 GMT) the Central Interconnected System collapsed after a 500 KW transformer at the Charrua substation in Bio Bio, 420 miles (675 kilometers) south of Santiago tripped. It resulted in most of the country, including the capital Santiago, plunging in darkness.
Power has since been restored in 98 per cent of the country, but authorities said in some zones the service would remain unstable.
For comments and feedback: editorial@rttnews.com