At least 76 police officers were hurt in clashes with anti-G20 protestors in Hamburg, Germany, on Thursday. German Police clashed with a group of masked anti-capitalist activists hurling bottles and stones, ahead of the G20 Summit that begins on Friday, AFP reported.

German authorities said a demonstration dubbed “Welcome to Hell”, comprising nearly 12,000 protestors, began peacefully but turned violent soon after. “Police are still being attacked,” said a spokesperson for the Hamburg Police.

Three officers are being treated at a hospital, while the rest had sustained light injuries, reported Reuters.

Protestors damaged cars, set other objects ablaze and threw bottles during the clashes that lasted until midnight. The police said pilots of a police helicopter sustained eye injuries when laser pointers were directed at them. They had to use water cannons and teargas to disperse the crowd.

Up to a lakh demonstrators are expected before and during the two-day Group of 20 meeting.