Transcript for G-20 summit protesters clash with police

So much breaking news overnight. This morning wall eyes on that g20 summit in Germany. Those protesters on the streets of Hamburg. That's a look at them right now. Peaceful there but did get violent through the night. The first lady, Melania trump could not leave her hotel because of the violence in the streets. And there are pictures of the world leaders gathered. There's president trump and Angela Merkel of Germany. President trump the only leader there who has not signed on to the Paris climate accord. That will be on the agenda this morning. But today's key meeting, president trump, Vladimir Putin face-to-face for the first time, that was the handshake this morning with Angela Merkel and Putin. The president will be one-on-one on him in just a few hours and all this comes after a night of violent protests around the summit there. Thousands in the streets. Fires, tear gas and water cannons. ABC's James Longman is on the scene in Hamburg, good morning, James. Reporter: Good morning, George. I'm at the police perimeter that surrounds the g20 summit and small protests like these have been happening all morning but follow a violent evening. Overnight, 8,000 protesters gathered. Most peaceful but many intent on violence. Setting cars on fire, police using high pressured water cannons to keep them back. Watch as police in riot gear move in on the fire-filled streets. This Porsche car dealership looted. Tear gas striking the crowds. Welcome 2 hell. That's the name of the protest gripping the streets of Hamburg this morning. Protesters and authorities clashing. Bottles and rocks thrown. Over 70 police injured. Violence. I kind of feel pressure. Reporter: Protests always target g20 meetings but this year the stakes are higher than ever before as president trump comes to town. This is one of the main routes where leaders are arriving for the g20 summit and protesters are trying to block it and the police, water truck, they're trying to move people on. Up to 100,000 protesters are expected. 20,000 police officers dispatched. Major protests are expected to continue into the weekend and if last night was anything to go by, they could escalate. James, thanks for that.

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