Reports say that all but one of the deaths happened in the coastal province of Ica, which is about 265km (165 miles) south of Lima, the capital of Peru.
Peruvian president Alan Garcia said he would be sending three cabinet ministers to the towns most badly hit.
The US Geological Survey said the epicentre of the earthquake was beneath the Pacific Ocean, about 145km (90 miles) southeast of Lima, and they added that it is known that four strong aftershocks ranging from 5.4 to 5.9 followed the main quake.
Rush-hour traffic in the capital of Lima came to a standstill as buildings were shaken but the full force of the earthquake hit closer to the epicentre in the southern coastal province of Ica – buildings were brought down, and power supplies and communications were disrupted.
Low-lying areas on the coast in Peru, Chile, Ecuador and Colombia were evacuated after a tsunami alert was issued, although this was subsequently withdrawn.
