'Peripheral Figure': London Attacker Known To Authorities

New details have emerged in the brutal terrorist attack in London at the House of Parliament on Wednesday that left four people dead, including the attacker, and several others injured.

As RadarOnline.com previously reported, the killer drove a small SUV down Westminster Bridge in the British capital, plowing down pedestrians, two of whom died, before he crashed through a fence onto the government property.

Now, Prime Minister Theresa May says the suspect, British-born, was known to MI5 authorities and had been a "peripheral figure" who may have been inspired by Islamist ideology. He has not been named yet.

According to law enforcement, those fatally wounded in the attack were Keith Palmer, 48, the police officer who was stabbed outside Parliament, and two civilians — a teacher in her 40s and a man in his 50s.

"Our investigation is ongoing — developing all the time — and is focused on the attacker's motivation, his preparation and associates," Mark Rowley, the acting deputy commissioner of the London Metropolitan Police, announced.

Meanwhile, a witness to the London terrorist attack described their horror as the incident unfolded.

"We were taking photos of Big Ben and we saw all the people running towards us, and then there was a guy in about his 40s carrying a knife about seven or eight inches long," Jayne Wilkinson told the Daily Mail. "And then there were three shots fired, and then we crossed the road and looked over. The man was on the floor with blood."