At least 70 people have been killed by wildfires that have ravaged several Mediterranean countries this week.

In Algeria, the death toll climbed to 69 on Wednesday, according to AFP, as firemen, soldiers and civilian volunteers battle blazes in forests across the country's northern regions that began Monday.

Algerian President Abdelmadjid Tebboune declared three days of national mourning starting Thursday, and authorities say they suspect widespread arson after many fires erupted in a short space of time. 

In southern Italy, fire has burned thousands of acres of land in recent weeks.

According to ANSA news agency, a 76-year-old man in southwestern Calabria was the latest victim as he died after his house collapsed due to the flames.

So far, two people have died in Calabria and one in Sicily, according to local media.

In Greece, three people were killed and hundreds left homeless due to fires on Evia, the country's second largest island just northeast of the capital Athens over nine days.

Greek officials have pointed the finger at climate change, which experts say increases the intensity and frequency of such extreme weather events.

(With input from agencies)