Heavy rains on the islands of Kefalonia and Zakynthos led to flooding, BNR reported.
In places the water reached one meter. Ground floors of houses and shops were flooded. The road network was severely affected. Police reported that many roads on both islands were closed by rock slides.
The Civil Protection Department is urging residents and tourists to avoid traveling.
On the island of Kefalonia, the water washed away bridges and damaged roads. A state of emergency is expected to be declared by the end of the day. People are advised to stock up on food and water for several days, authorities recommend. Firefighters rescued people trapped in ground floors by the water.
The heavy rains will continue today, affecting the Peloponnese and the islands in the Aegean Sea. Hail is expected in some places.