The aftershock hit 14 miles (23 kms) south of the port city of Iquique.
A tsunami warning was in effect for Chile and Peru, according to the Pacific Tsunami Warning Center, but was later canceled.
There were no immediate reports of damage.
Tuesday's quake prompted coastal evacuations and tsunami warnings for neighboring nations. Five people reportedly died in the aftermath, including three people who were crushed by falling debris. Two others died of heart attacks.
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