Transcript for 4 killed including suspect, at least 29 hospitalized in London terror attack

And you're right now at London, the scene of that devastating terror attack. Here is what key know right now. At least three victims were killed. 29 injured. Authorizes believe the suspect was a lone wolf. He was also killed in the attack and there were raids overnight across the uk leading to at least eight arrests. And cities around the world are standing in solidarity with London. Orlando, tel aviv and more lighting monuments in the union jack's colors and others like the eiffel tower going dark to pay tribute to vics. Yes, we do have team coverage. Our cheern foreign correspondent Terry Moran starts us off from London. Good morning, Terry. Reporter: Good morning, robin. It is an eerie scene, this heart of London. Usually such a bustling area but now a crime scene. This is where it ended. Right there under the shadow of big Ben where the attacker was killed and we know now he was British born. Homegrown terror inspired by islamist ideology and acting alone although authorities are withholding his identity. Up in Birmingham resulting in eight arrests as authorities try to get to the bottom and unravel the worst terrorist attack in the United Kingdom in more than a decade. Mayhem in the streets of London. The moment the terrorist attacks. Tourists fleeing gunshots at parliament. Victims strewn across the Westminster bridge. Bystanders frantically trying to save the wounded. The attack unfolded 2:40 Wednesday afternoon. You can see a gray Hyundai barreling down the packed bridge aiming for pedestrians. One woman falling or jumping off the bridge there. That woman seriously injured but this morning she's alive. A car speeding up straightaway. The first hit even the second people and the third time he was doing, no one realized it. As he done it in and out zigzag. Reporter: Crashing into a railing just outside parliament before fleeing his car charging the Gates and stabbed an unarmed police officer who confronted him. Police then shooting the attacker. There were bodies literally -- in must have been about 10. Reporter: Tourists trapped in the London eye watching the carnage unfold below. More sirens so I knew something big happened. Reporter: This American born politician Tobias Ellwood trying to save that police officer. Performing cpr and giving him mouth-to-mouth resuscitation. Inside the government on lockdown. This house is now suspended but please wait here. Reporter: Britain's prime minister rushed away to safety later addressing a shocked nation. The likes of this attack was no accident. The terrorist chose to strike at the heart of our capital city. Reporter: In all three were killed and the assailant was killed and at least 40 injured including a group of French teenagers on a class trip. It was super hectic. You could see people running around. People looked scared. Reporter: Among the deceased that brave police officer Keith palmer, a 15 year-veteran stabbed and succumbing to his injuries. So, while police are still processing this vast crime scene, one final note, parliament is back at business under big Ben in the houses of parliament there. A sign they will not be cowed. We are not afraid is the slogan you hear again and again around London today. Amy. All right, Terry, thank you.

This transcript has been automatically generated and may not be 100% accurate.