GENEVA (AP) — Riot police fired tear gas and water cannons in clashes with stone-throwing youths during a protest on Sunday in Geneva against the G7 group of wealthy nations, a day before its leaders including U.S. President Donald Trump hold a summit in nearby France.

A violent standoff extended into the evening after a series of incidents — including a car set ablaze and a bank's windows smashed — along the route of an afternoon march that drew an estimated 20,000 people, including some 600 so-called "Black Bloc" militants, according to figures from Geneva police spokesman Alexandre Brahier.

The demonstration, which had been previously organized by a hodgepodge of activist groups after weeks of negotiations with local authorities, was otherwise peaceful — with environmentalists, women's rights advocates, supporters of Palestinians and foes of imperialism, fascism and capitalism.

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Early on during the march, firefighters extinguished a Tesla that was set ablaze next to the central bus stop and a phalanx of riot police cordoned off a secure area as a crowd congregated nearby.