In an address to the nation, President Michelle Bachelet said two million Chileans had been affected but, after touring the worst-hit areas by plane, she found it hard to spell out the magnitude of the disaster.
"The power of nature has again struck our country," Bachelet said, declaring six of Chile's 15 regions "catastrophe zones" in the aftermath of the 8.
8-magnitude quake.
Highways in the South American nation of 16 million were sliced to pieces, bridges imploded and buildings collapsed as the 8.
8-magnitude earthquake struck overnight some 325 kilometers (200 miles) southwest of the capital Santiago.
"This is a catastrophe of immense proportions, so it will be very difficult to give precise figures," Interior Minister Edmundo Perez Yoma said. Officials later said at least 300 people had been killed.
Waves well over two meters high (seven feet) crashed into the Chilean coast after the quake struck at 3:34 am (0634 GMT) and tore out into the Pacific, killing at least five people