In pictures: London attack aftermath

The flag above the Houses of Parliament flies at half mastJonathan Brady/PA

The flag above the Houses of Parliament flew at half mast following Wednesday's attack on Westminster that left five people dead, including the attacker, and many injured.

Police activity on Whitehall in LondonJonathan Brady/PA Wire

The attacker, identified as Khalid Masood, 52, drove a car along the pavement on Westminster Bridge, knocking down pedestrians, before killing a policeman in the grounds of Parliament.

A member of the public lays flowers outside New Scotland YardWill Oliver / EPA

Members of the public brought flowers to lay outside New Scotland Yard in tribute to PC Keith Palmer.

A flower tied to police tape outside the Queen Elizabeth II Centre in LondonGareth Fuller/PA

Others left them near to the scene of the attack in Westminster.

Members of the House of Parliament observe a minute's silencePA

Members of Parliament held a minute's silence in Westminster on Thursday morning.

A minute's silence is observed outside New Scotland YardJonathan Brady/PA

And a silence was also held outside New Scotland Yard.

Police forensic officers in Parliament Square outside the Houses of Parliament in LondonDominic Lipinski/PA

Officers continued to search the area for forensic evidence.

British Prime Minister Theresa May leaves 10 Downing StreetJack taylor / AFP

Prime Minister Theresa May said there was no reason to believe there would be imminent further attacks. She also said the UK's threat level was set at severe, and would not change.

Pedestrians and a cyclist cross Westminster BridgeAdrian Dennis / AFP

Westminster Bridge reopened less than 24 hours after the attack.

Armed police officers patrol outside Westminster underground stationDarren Staples / Reuters

Armed officers remained very visible around the area.

British Transport Police officers pause after laying floral tributes on Westminster BridgeJack Taylor/Getty Images

Members of the British Transport Police paused for a moment after laying floral tributes on Westminster Bridge.

A man pauses in front of floral tributesDaniel Leal-Olivas / AFP

A man pauses in front of floral tributes laid in honour of PC Keith Palmer at the National Police Memorial in Westminster. In a statement, the PC's family said he was a "friend to everyone who knew him".

People gathered in Trafalgar SquarePA

People gathered in London's Trafalgar Square on Thursday to pay their respects to those who were injured and killed in the attack.

Two women lighting candlesReuters

The candlelit vigil in Trafalgar Square was also marked by speeches, including one by Mayor of London Sadiq Khan, who described the city as "full of amazing people from all backgrounds, and when Londoners face adversity we always pull together".

(From left) Archbishop of Canterbury, the Most Reverend Justin Welby, Chief Rabbi Ephraim Mirvis, Sheikh Khalifa Ezzat, Sheikh Mohammed al Hilli and Cardinal Vincent Nichols, Archbishop of WestminsterEPA

On Friday, inter-faith leaders held a vigil in the grounds of Westminster Abbey.

Archbishop of Canterbury, Justin Welby, embracing Sheikh Khalifa Ezzat, chief Imam and head of religious affairs at the London Central Mosque.Getty Images

The Archbishop of Canterbury, the Most Reverend Justin Welby, is seen during the vigil embracing Sheikh Khalifa Ezzat, chief Imam and head of religious affairs at the London Central Mosque.

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