One minister said that about half of the fires were "apparently arson," but this has not been confirmed by law enforcement.
No deaths or serious injuries have been reported but the national ambulance service say about 35 people have been treated for smoke inhalation as hundreds of military reservists have been activated to help fight the three-day outbreak.
Schools, kindergartens, retirement homes and the University were evacuated.
The Mayor of Haifa, Yonah Yahav told Channel 2 TV that there was some evidence that one of the fires began when "someone tossed a cigarette in an area full of oil and flammable fluids" in an industrial area.
Highway 443 linking Jerusalem and Tel Aviv was closed to morning traffic on Thursday after another fire reached the city of Modi'in.
About 300 students were evacuated from a school in a settlement known as Talmon, and homes and cars were damaged in the blaze.
Cyprus, Italy, Russia, Croatia and Greece have sent help and equipment, including aircraft, to help tackle the blazes.
Four Palestinians have been arrested and are to appear in court on suspicion of starting a bonfire 'negligently'.
"Almost 50% of the fires are apparently arson," Internal Security Minister Gilad Erdan told Army Radio.
Education Minister Naftali Bennett, the leader of the Jewish Home party, Tweeted (in Hebrew): "Only those to whom the country does not belong are capable of burning it."
The Arabic-language hashtag #Israel_on_fire began trending and most of the tweets expressed pleasure and satisfaction over the outbreak of fires.
Here's a question: if being Islamophobic in America is considered to be racist, why isn't being anti-Semitic also being racist?