A 6.7-magnitude earthquake, the latest in a series of powerful tremors, was registered in western Chile on Tuesday, the U.S. Geological Survey said.

The quake, with the epicenter at the depth of 35 km (21.7 miles), stroke at 02:22 GMT some 75 km (50 miles) north of the western Chilean city of Concepcion.

There were no immediate reports on causalities or damage. No tsunami alert was issued.

Some 150 tremors, about 20 of them powerful, have been registered in Chile since an 8.8-magnitude earthquake occurred to the north of Concepcion. According to official reports, 497 people died as a result of that tremor.

It was followed by a series of aftershocks and tsunamis leaving some 2 million Chileans homeless and damaging about 1.5 million houses.

Chile''s newly-elected President Sebastian Pinera has said it would cost at least $30 billion to rebuild the country after the devastating earthquake.