Gilad Erdan said up to 50 percent of the fires in recent days had been deliberate, labelling it "arson terror."
Netanyahu did not say whether he believed the six fires in the northern city of Haifa and others were caused by arsonists, but said his government had noticed "encouragement to arson" on social media.
"Every fire caused by arson or incitement to arson is terror and will be treated as such accordingly," he told reporters in Haifa near the scene of the fires.
More than 60,000 people have been evacuated from their homes in Haifa, its municipality said, while other fires broke out occurred up near Jerusalem and other parts of Israel.
Meteorologists say the dry weather and strong winds mean conditions are perfect for fires to spread -- whether sparked by accident or on purpose.
Internal Security Minister Gilad Erdan said up to 50 percent of the fires in recent days had been deliberate, labelling it "arson terror."
"It is clear that many fires started as deliberate arson."