SANTIAGO, Chile (AP) - A strong earthquake struck northern Chile early Friday, briefly knocking out power to a city but otherwise causing no major damages, authorities said.

The 6.5-magnitude quake's epicenter was between the cities of Iquique and Arica, about 60 miles (95 kilometers) from each, according to the U.S. Geological Survey. It hit just after midnight Friday local time (0305 GMT Friday; 10:05 p.m. Thursday EST).

Chile's National Emergency Office put the quake's magnitude at 5. It was unclear why the readings were different.

The office said the quake knocked out electricity in the city of Iquique but power was restored in minutes.

The quake had a relatively shallow depth of 6 miles (10 kilometers), according to the USGS.

Powerful earthquakes are common in the South American nation, which stretches along the quake-prone Pacific "Ring of Fire."

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