Friday's quake was considerably less violent in Lima, a city of 8.5 million people. The capital shook for about 30 seconds in a series of moderate, swaying movements.
Several aftershocks followed with magnitudes up to 5.5, said the U.S. Geological Survey.
It said Friday's quake was centered 31 miles (51 kilometers) south-southwest of Ica, a provincial capital of about 200,000 people which suffered widespread damage in the 2007 quake. It was at a depth of 21.7 miles (35 kilometers).
The directors of two hospitals in Ica told RPP that 20 people were treated for non life-threatening injuries including two for broken bones.
Peru's government-run Institute of Geophysics put the quake's magnitude at 6.7 and put its depth at 19 miles (30 kilometers). The USGS said the killer 2007 quake was centered 24 miles (39 kilometers) deep.
A seismologist at the institute, Hernan Tavera, told RPP the 2007 quake released 33 times more energy than Friday's temblor but this time " the radius of action was far wider."
"There was panic, a lot of panic," said Ruben Vargas, a police official in Ica, which is flanked by asparagus fields and vineyards that produce wine and the liquor pisco.
Vargas said that many people were still in the streets nearly a half hour after the 1:54 p.m. (18:54 GMT) quake. "Little by little people are calming down but they're still outside their homes," he added.
In Pisco, police officer Julio Lopez said people were spooked though the quake wasn't nearly as bad as the 2007 temblor.
"It wasn't like the last time. It was shorter," said Jorge Luis Yupanqui, 30, from Pisco. "Some people started to cry."
He said there was a big traffic jam in Pisco because he, like many others, went home to make sure his family and home were safe.
About 40,000 homes were destroyed in the 2007 quake and the previous government of President Alan Garcia was widely criticized for the slow pace of reconstruction.