At least 20 people were injured and four have reportedly died when a car mowed through a crowd on Westminster Bridge at around 2:30 PM.
The suspect continued to drive towards Parliament when the attacker got out of the car with a knife and attacked a police officer before being shot dead. The officer who was stabbed has died from his injuries.
Three police officers on their way back from a commendation ceremony and three students visiting London from France were among those injured by the car.
A photo of the attacker being tended by medics
The deceased include the police officer, two pedestrians and the attacker.
A number of people are being treated for "catastrophic" injuries. Sky News reports that one woman was killed when the attacker ploughed his car into pedestrians on the pavement of Westminster Bridge.
According to Express, “a suspicious package was then discovered at Parliament sparking an evacuation.”
The attackers were described by witnesses as being middle-aged Asians. “Asian” in the UK can also mean Middle Eastern.
Watch the terrifying moment police opened fire outside of #Parliament in this eyewitness video captured by Taiwanese tourist Aaron Tsang pic.twitter.com/WrCVhWPrFK— Yahoo UK News (@YahooNewsUK) March 22, 2017
Vehicular jihad has become a popular terrorist method, as seen in Germany and France.
We will keep this story updated as more information develops.