Transcript for London terror attack: Police raid 2nd home

We're learning tonight about that subway bombing in London. Tonight we have new surveillance video report early taken the morning of the incident it's just come in. And now the arrest of a second suspect in that attack that terrorized morning commuters here's ABC's Ian panel. Tonight's is this that London bomb up. Major surveillance video emerging from the morning of the attack showed a man leaving a house late two raided by counterterrorism police. Carrying the exact same type of shopping back used to hide the bomb. The house connected to an eighteen year old arrested Saturday in the port city of Dover investigates is calling that development significance. He was arrested on suspicion of being consent to the commission. Preparation. Or instigation of acts of terrorism. Tonight he's being held in London. This weekend offices swooping into this normally peaceful neighborhood in southwest London. Davis in the area given two minutes to leave their homes for their own safety as police moved in I was scared for to be honest I was really scared. That's home just twelve miles from the song to the explosion. And a second arrest was made after that subway bombing suggesting the tackle wasn't acting alone. A 21 year old man taken by anti terrorism police just people make nice. Aerial footage showing please securing the home which is just a few hundred feast from Heathrow airport's. ABC news learning to homemade device detonated a Parsons green injuring thirty contained T ATP. An exclusive made from hydrogen peroxide commonly sold as add bleach and other chemicals. It's a highly unstable compound as being used in terror attacks be full. From Paris to Brussels including the man just Arianna grundy clones of bombing to kill 22. So tonight's the terror threat level has been lowered from critical to severe which still means the police hit think another attack highly likely. As commutes is prepared to get on the same subway trains going to work and going to school tomorrow morning. Home some no doubt we'll definitely be on edge all right Ian thing.

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