Thousands of police lined the streets of central London as they said farewell to terror attack hero and fellow officer Keith Palmer.
PC Palmer's body was taken from a chapel in Westminster, where he laid in rest overnight after the Queen gave special permission, to Southwark Cathedral for his funeral.
Around 5,000 officers from the Metropolitan Police and other forces around the country stood along the 2.6-mile route and bowed their heads in silent tribute as the cortege passed.
Flowers containing the words No 1 Daddy were laid on the hearse as the funeral procession made its way to the cathedral.
Some members of the public and police shed tears, while PC Palmer's family and friends followed the hearse in black cars behind.
The 48-year-old father and husband was stabbed to death by Khalid Masood as the terrorist tried to get into Westminster after running through an entrance and into a courtyard in the grounds.
PC Palmer was one of five people killed during the attack which began when Masood drove his rental car at high-speed into pedestrians on the pavement of Westminster Bridge.
The other victims were Andreea Cristea, 31, Leslie Rhodes, 75, Kurt Cochran, 54, and 44-year-old Aysha Frade.
Masood was shot dead.
The procession was led by mounted officers from the Met before the coffin was carried into the cathedral by colleagues and friends of PC Palmer.
Rows of officers in dress uniform, many displaying service medals, lined up on nearby streets as on-duty colleagues stood guard during the massive security operation.
Around 50 members of PC Palmer's family including his wife, child, mother and father, brother and sisters, were among mourners at the service.
Scotland Yard's first female chief in its 188-year history, Met commissioner Cressida Dick, was also there in her first public engagement in her new role.
Ms Dick read the WH Auden poem Funeral Blues, which begins "Stop all the clocks, cut off the telephone", and asks for "the traffic police men to wear black cotton gloves" in mourning of a loved one.
In reference to the poem, the Met's senior chaplain, the Reverend Prebendary Jonathan Osborne, said: "Keith died doing his duty, and it was as if in those moments the clock stopped."
He said PC Palmer had "laid down his life for each one of us" when he intercepted Masood during the attack.
Officers bowed their heads as the Last Post sounded from the cathedral.
Members of the public outside were able to watch proceedings on screens outside.
The service was followed by a private cremation.
Additional reporting from IRN
