More than 150 people suffered injuries, the majority of them minor, and 200 homes were damaged.
One victim was found dead after the roof of his house collapsed in the village of Kato Achaia. An 80-year-old woman also died from injuries sustained due to the shaking.
The quake, which was felt as far away as southern Italy and the Greek capital of Athens, caused panicked residents to rush onto the streets.
Television reports said many people spent the night outdoors and in cars in fear of aftershocks.
The country’s Geodynamic Institute warned residents that strong aftershocks would be possible for several days near the epicenter of Sunday’s temblor.
Institute seismologists estimated the strongest aftershocks could range in magnitudes between 5.0 and 5.5.
The National Observatory of Athens said Sunday’s quake occurred at 3:25 p.m. local time about 130 miles (205 km) west of Athens near the town of Andravida. Seismologists said the epicenter was at a depth of about 6 miles (10 km).
