Six days of riots over the police killing of a teenager has caused some 20 million euros in damage to public transport in the Paris region, the regional operator said Monday.

This includes "burned buses, a torched tramway, two damaged tramways and urban infrastructure which was smashed," the authority for the Ile-de-France regional transport network said in a statement.

Turkish President Recep Tayyip Erdogan blamed France's nationwide riots on "institutional racism" and the country's colonial past.

The French government has been battling riots and looting in Paris and across the country since 17-year-old Nahel M -- a French citizen of Algerian background -- was shot dead by a police officer during a traffic stop last Tuesday.

He blamed the French unrest on Islamophobia which he linked to France's colonial past.

"In countries known for their colonial past, cultural racism has turned into institutional racism," he said on television, after chairing a weekly cabinet meeting.

"At the root of the events that started in France is the social architecture built by this mentality. Most of the immigrants who are condemned to live in ghettos, who are systematically oppressed, are Muslims."

He also condemned the widespread looting that has accompanied the unrest.

"The streets cannot be used to seek justice. However, it is clear the authorities should also learn from the social explosion," Erdogan said.