A ‘SICK and depraved’ terrorist killed three people and injured 29 in a rampage on Parliament that knifed Britain in the heart.

Theresa May condemned the maniac who mowed down pedestrians in London “at 70 mph” on Westminster Bridge before storming Parliament and stabbing a police officer to death.

38 Armed cops draw their guns on a suspected attacker after a knifeman went on a rampage mowing down pedestrians, injuring 29 Credit: PA:Press Association

38 PC Keith Palmer who was stabbed to death by a suspected terrorist outside the Palace of Westminster Credit: PA:Press Association

38 A man - thought to be the terrorist behind yesterday's attack - is wheeled onto an ambulance Credit: PA:Press Association

38 MP Tobias Ellwood gives CPR to a police officer stabbed outside Parliament Credit: PA:Press Association

38 The suspect lies on a stretcher outside Parliament with paramedics treating his injuries while armed cops stand guard Credit: PA:Press Association

38 One of two knives thought to have been used by the suspect to stab a cop during the terror attack Credit: PA:Press Association

The heroic cop who tried to stop the attacker was named as married father PC Keith Palmer.

Also among the victims was Aysha Frade, 43, who is believed to have been killed as she travelled to pick her children up from school.

Speaking the morning after the devastation, the PM admitted the British-born lone-wolf attacker had previously been investigated by MI5– but had been dismissed as a "peripheral figure".

38 PM Theresa May says we will 'never give in to terror' following Westminster attack Credit: PA:Press Association

38 An image from the scene shows two knives on the ground as paramedics treat a suspect Credit: PA:Press Association

38 Emergency services treat two people - thought to be the attacker and injured cop - outside Parliament following the attack Credit: PA:Press Association

38 A car crashed into gates outside Parliament after mowing down up to a dozen people on Westminster Bridge causing carnage in the capital

The large-scale terror attack has exposed critical flaws in the security of Westminster, as MPs said the killer ran through a “weak spot” and got 25 yards inside the gates.

Shocking footage emerged of the attacker’s car, a year-old Hyundai Tucson registered in Chelmsford, Essex, ploughing into pedestrians on Westminster Bridge, forcing one woman to jump into the Thames to escape.

Witness James Sheriff told the Times "he must have been going at 70mph".

The car used to carry out the slaughter – on the anniversary of the Brussels airport attack - was hired last Thursday in Birmingham, according to Newsnight.

Terror cops arrested eight people in raids on six different addresses across London and Birmingham in connection with the atrocity.

The Prime Minister, who was bundled into a silver Jaguar and rushed from the scene, said it was "no accident" the terrorist struck "in the heart of our capital".

Speaking after a Cobra meeting, she said: "The terrorist chose to strike at the heart of our capital city.

“The values our parliament represents - democracy, freedom, human rights, the rule of law - command the admiration and respect of free people everywhere. Any attempt to defeat those values through violence and terror is doomed to failure."

38 A woman trapped under a bus after the attack in London Credit: Reuters

38 A woman helps a victim of the terror attack which a car plough down pedestrians on Westminster Bridge Credit: Reuters

38 Witnesses rushed to help a victim with reports that a car mowed down a number of people on Westminster Bridge before crashing into the gate outside Parliament Credit: Reuters

Mark Rowley, national lead for Counter Terrorism Policing and Met Acting Deputy Commissioner, said the attacker was “inspired by Islamic terrorism”.

He added that hundreds of police officers were involved in the investigation to check his background and trace his known associates.

Dramatic pictures show the bloodied bodies of victims littering Westminster bridge as heroic bystanders desperately try to save the lives of those "catastrophically" injured.

Among them were MP Tobias Ellwood who gave PC Palmer mouth-to-mouth. Ellwood's brother was killed in the Bali bombings in 2002.

38 Heroic bystanders rushed to help those ploughed over on Westminster Bridge this afternoon Credit: Reuters

38 A victim lies at the foot of stairs on Westminster Bridge after this afternoon's attack Credit: Reuters

38 A man is treated on Westminster bridge by bystanders Credit: Reuters

38 An injured man is assisted after the incident on Westminster Bridge Credit: Reuters

The 50-year-old Foreign Office Minister and Conservative MP said: "It is a huge tragedy, it really is.

"I tried to stem the flow of blood and give mouth-to-mouth while waiting for the medics to arrive but I think he had lost too much blood.

"He had multiple wounds, under the arm and in the back."

MP James Cleverley tweeted: "I've known Keith for 25 years. We served together in the Royal Artillery before he became a copper. A lovely man, a friend. I'm heartbroken."

One Romanian tourist suffered serious injuries after she was thrown into the River Thames in yesterday's attack.

Others were tossed into the path of oncoming traffic, including one woman who was seen lying under a bus.

38 A bloodied victim is pictured at the scene in Westminster Credit: Reuters

38 A doctor walks from the scene with his hand on his head after the attack Credit: Getty Images

Speaking to reporters junior doctor Colleen Anderson from St Thomas' Hospital said a female pedestrian had died.

She said: "I confirmed one fatality. A woman. She was under the wheel of a bus. She died, confirmed her death at the scene."

The Metropolitan Police opened a Casualty Bureau for those worried about friends and family.

38 A man is treated by paramedics at the scene Credit: Getty Images

38 One woman is tended to by paramedics and cops after being injured on Westminster Bridge Credit: Getty Images

38 A woman is stretchered onto an ambulance after the attack Credit: Getty Images

London mayor Sadiq Khan said: “London is the greatest city in the world and we stand together in the face of those who seek to harm us and destroy our way of life.

"Londoners will never be cowed by terrorism."

38 Londoners have been asked not to call emergency services unless absolutely necessary as they tend to victims Credit: Getty Images

38 A victim is treated by paramedics and wrapped in a foil blanket as he explains to officers what he saw Credit: Getty Images

38 At least 20 people were injured when an attacker ploughed his car into pedestrians on Westminster Bridge and stabbed a police officer Credit: Getty Images

38 Credit: PA Graphics

The motivation for the attack is not yet known but ISIS supporters celebrated the horror on social media, dubbing it "revenge" for UK strikes in Mosul.

Those celebrating the attack, which had similarities with atrocities in Nice and Berlin, called it "blood for blood".

The attack came on the first anniversary of the Brussels airport bombings.

The Muslim Council of Britain said: "We are shocked and saddened by the incident at Westminster. We condemn this attack and while it is still too early to speculate on the motives, our thoughts and prayers are for the victims and those affected.

"We pay tribute too to the police and emergency services who handled this with bravery."