Transcript for London Attacks: Brave Mother Confronted Hacking Suspects
We're getting our first look at the moment -- police in London arrive to confront the to a terror suspects who had allegedly just murdered a young soldier in cold blood. And in broad daylight this is... See More
We're getting our first look at the moment -- police in London arrive to confront the to a terror suspects who had allegedly just murdered a young soldier in cold blood. And in broad daylight this is an attack that has genuinely shocked the world. Today we learn a lot more about the suspects of their victim and a brave woman who just happen to be there on the scene. Or -- start tonight though with that new video and we -- you. It is graphic here's ABC's llama Hasan. Two attackers taking down by police in the month after a nightmare attacked in broad daylight and all -- -- British soldier viciously hit by car and then hacked to death. By men armed with meat cleaver is denies shouting god is -- Moments later one of them has covered in blood invites -- bystanders. To film him. No public. One of the attackers as being identified as 28 year old Michael -- -- closure. He is a Muslim convert that Nigerian defense. The body of 25 year old -- Rigby an Afghan war vet and father of a two year old was left in the middle of the streets. After heat was brutally stabbed. As if to maximize its parent one of the attackers -- even -- people to cool Japanese luring them into shootouts. The final moments captured on -- self as shots rang out. Video -- the police gunning down NT suspects in the street when -- and Yang -- That's walked on allies -- backed -- but even before -- intervened some citizens who ran toward the scene trying to aid the dying soldier. It's -- -- -- not politically it's -- about twenty minutes. And if we're likely to -- not a good parts I'm out here. He was stunned -- every night. Amidst the horror heroes emerged like cub scout leader Ingrid though you can -- She had rushed to give first aid in vain and then defiantly confronted the attacker. I could see a -- there a butcher's knife and dead -- -- -- half of work to heck happened to be asking you to use him enough snow in plain don't -- to -- on the charge because. And for Disneyland -- all mothers with children stumping around by say wasn't even one more important that I took two Hammond and then knocked him what he wanted -- What is she earned -- -- the prime minister David Cameron when told by the attack. He wanted to start a war in London. She replied. You'll going to lose it is only EU vs many. She spoke for -- so it is the brazen brutality and unsophisticated. Nature of the attack that sets us apart and has left many questions. It's almost impossible to know in these attacks are going to occur. It's almost impossible to stop them. You cannot intercept orders going to the attackers because the attackers themselves decide when and how to attack. You can't stop them from getting the weapons because -- weapons can be obtained in any store. And the killers appear to fit an all too familiar passer. Homegrown radicalize young men almost impossible to detect -- Authorities in both the United States in the United Kingdom have long feared the possibility. Of this sort of thing happening. Radicalized. People living in the country citizens perhaps of the country. Who suddenly shift. From -- radicals -- being violent. The attacker Michael undergo those -- can be -- speaking in South London accents. Partly apologizing. Even refers to British soldiers and -- let's get our troops. Reported he was known to the British security services but crucially something was missed. He even can be seen here demonstrating in 2007. -- -- -- -- -- -- -- -- -- -- Very very. Calm but I did this evening you'll find -- But he was reportedly arrested at a violent demonstration in 2006. Outside London's High Court. -- jury last saw him two years ago. He was someone studying his own religion -- -- -- -- you know somewhere else. I'm the next thing we know we have -- Unsophisticated. Though and attackers in London like the two alleged terrorist Brothers who set off bombs at the Boston narrative. Hitting three and virtually shutting down a major American city for days. But the type of challenge and law enforcement is increasingly faced with. When they he'll have to build most sophisticated bomb. -- or have a lot of dry runs for the attack when they don't tell anybody that they're going to do it. It's virtually impossible for police or for intelligence. Authorities to know about it. -- -- Tonight in London there had been two additional arrests following a series of police raids at several locations around the country. One close to the murder -- An additional twelve -- companies have been dropped it on to London streets the attackers remain under armed guard reported -- in separate hospitals. As with Boston Police will want to determine if this brutal attack was part of a wider applause or whether this was a local -- acts of terror. Tonight as a memorial grows at the side of the attack he read these family pay tribute to their fallen sons saying. He would do anything for anyone all he wanted to do from when he was little boy was -- in the army. For Nightline on -- has sent in London.
This transcript has been automatically generated and may not be 100% accurate.