- Police clash with group of 1,000 black-clad anarchists
- 75 police officers injured
- About 100,000 protesters expected during summit
German police have used water cannons and pepper spray to disperse protesters in Hamburg after being attacked with bottles and stones by marchers protesting about the G20 summit.
About 75 police officers were injured throughout the evening clashes, with three requiring treatment in hospital, police said.
The pilots of a police helicopter sustained eye injuries when laser pointers were directed at them, police said.
The clashes erupted near the summit venue on Thursday (local time), less than an hour after Chancellor Angela Merkel met US President Donald Trump.
Police said they repeatedly asked a group of hardcore anti-capitalist demonstrators to remove their masks, to no avail.
They fired water cannons at black-clad protesters after they threw bottles and bricks, breaking the window of a police vehicle.
A nearby building was plastered with the slogan: “Borderless solidarity instead of nationalism: attack the G20.”
A small group on the roof set off fireworks. Police said windows at a furniture store and a bank were damaged.
There was no immediate word on the number of arrests.
Thousands of protesters from around Europe, who say the G20 has failed to solve many of the issues threatening world peace, poured into Hamburg ahead of the talks.
Police expect about 100,000 protesters in the port city, some 8,000 of whom are deemed by security forces to be ready to commit violence. Up to 20,000 police officers are on hand.
At least 13,000 protesters joined the main march on Thursday, including about 1,000 black-clad anarchists, police said.
“Welcome to hell” was the protesters’ greeting for Mr Trump and other world leaders arriving for the two-day meeting.
The chaos tarnished the outset of the meeting Ms Merkel hopes will cement her role as a stateswoman as she seeks re-election in September.
The summit, which starts in full on Friday, is a chance for her to polish her diplomatic credentials but would be disastrous if marred by violence.
Ms Merkel has taken a high-risk gamble by choosing to hold the summit in the northern port city of Hamburg, partly to show the world that big protests are tolerated in a healthy democracy.
Before meeting Mr Trump, she struck a consensual tone, holding out hope for agreement on the divisive issue of climate policy and pledging to broker compromises.
She pledged to represent German and European interests at the summit, but added: “On the other hand, as hosts we — and I — will do all we can to find compromises.”
Mr Trump faces a testy confrontation at the summit with leaders of the other big Group of 20 economies after deciding last month to pull the United States out of the 2015 Paris climate deal.
Agreement could yet be found on climate, Ms Merkel indicated.
“There are various options, which can be discussed. We know that the United States have withdrawn. All others … or as far as I know, many, many others stand by this agreement,” she said.
She and Mr Trump discussed G20 themes, North Korea, the Middle East, and the conflict in eastern Ukraine, a German government spokesman said.
Mr Trump, who earlier in Poland called again on NATO partners to spend more on defence and said he would confront the threat from North Korea, is also due to hold his first face-to-face meeting with Russian President Vladimir Putin on the sidelines of the summit.
Their meeting, scheduled for Friday, will be closely watched at a time when mutual ties remain strained by US allegations of Russian election hacking, Syria, Ukraine and a US row over Mr Trump associates’ links to Moscow.