UPDATE: Four people, including a London police officer and the alleged assailant, have been killed and 20 injured from the attack. Among the injured were three police officers.
According to ABC, eight people were arrested during overnight raids at six locations including in Birmingham and London. The officer who died was 48-year-old Keith Palmer. Palmer was a husband and father and served for 15 years with the Metropolitan Police. He was not armed at the time.
Britain's Parliament is in lockdown after a police officer was stabbed and a car mowed down at least five people on Wednesday, March 22, the BBC reports.
According to the Press Association, the alleged assailant who stabbed the officer was shot by armed police. The driver of the vehicle, meanwhile, reportedly struck a group of people on Westminster Bridge.
The Metropolitan Police were called around 2:40 p.m. local time. The official Twitter account for the police tweeted that they are "treating this as a terrorist incident" until further notice.
According to reports, some people are severely injured in the area, and an air ambulance is attending the scene.
Prime Minister Theresa May was in the division lobby at the time and left in a car when she was alerted about the situation. Others in the House of Commons have been told to stay in their chambers and keep away from windows.
Police have also told the public to avoid Parliament Square and Lambeth Bridge.
Story is still developing.
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