Santiago, Chile: Thousands of people were evacuated from coastal areas in southern Chile on Sunday following a powerful Christmas Day earthquake that initially triggered a tsunami alert, later eased by officials.

The quake registered 7.7 on the Moment Magnitude scale according to seismologists at the US Geological Survey. Chile's national emergencies office ONEMI put it at 7.6.

There were no immediate reports of casualties, though electricity was cut to some communities.

Immediately after the quake, Chilean authorities issued a tsunami alert and urged people to flee the coast for high ground.

Later, the alert was downgraded to a "state of precaution" for several areas, according to ONEMI chief Ricardo Toro.

ONEMI said around 4,000 people had been evacuated from one town, Los Lagos. It maintained its order for the public to stay away from many beaches in the south.

The epicenter of the quake was on the southern part of Chiloe island, in a zone of several national parks. 

The Pacific Tsunami Warning Center in Honolulu, Hawaii, had given the depth of the quake at 15 kilometers (nine miles).

The closest population center was Castro, a town on the island of 40,000 inhabitants. Chile's capital Santiago was around 1,000 kilometers (600 miles) from the epicenter.

"The earthquake hit us as we were having breakfast and we immediately ran out of the house because of fears of a tsunami," one man who fled with his family told Chilean television.

Chilean media tweeted images of roads that had been cracked by the force of the quake. In some cases, part of the bitumen was cleaved away. 

- Families celebrating Christmas -

The quake struck as Chileans were were their families celebrating Christmas. All shops were closed.

Chile is in a quake-prone region, lying on the so-called Pacific Ring of Fire of frequent seismic activity. As a result, buildings are usually built to survive swaying.

The last big quake to shake Chile was in September 2015, when an 8.3 temblor followed by a tsunami hit the north of the country, killing 15 people. A coastal evacuation order had limited the number of casualties.

In 2010 another quake measuring 8.8, also followed by a tsunami, struck the center and south of the country, killing more than 500 people.