Prince Harry joined Sadiq Khan and the families of police officers who gave their lives in the line of duty for a memorial service.

Met commissioner Sir Bernard Hogan-Howe has paid tribute to Met Police officers and staff who have died while on duty, telling their families and friends "you do not remember and mourn alone".

At the annual service held in their memory at the Met’s training centre in Aerodrome Road, Hendon, Sir Bernard joined Prince Harry, Mr Khan and relatives of the fallen in laying wreaths and other floral tributes.

In the memorial garden at the training centre, Sir Bernard told those gathered that 650 officers and staff had lost their lives in the line of duty during the Met's 187-year history.

He said: “I know there is much sadness here today. No-one can ever underestimate the pain that so many of you here today live with day-to-day.

“But I hope it will bring you some small comfort to know that you do not remember and mourn alone.

“You are all members of the Met family and we stand together and remember with you.

“I hope you do take great pride in the fact that your loved ones died in the job that they loved, serving the communities of London.

“We are forever in their debt.”

Among the guests was Sid MacKay, 73, a former Chief Superintendent in the Met, whose daughter PC Nina MacKay was fatally stabbed at the age of 25 in 1997 during a raid in Stratford, east London.

Mr MacKay, who is the chairman of the Police Roll of Honour Trust, said: “You never expect to bury your child, that’s the most hurtful part.

“People talk about closure and I understand them using that term.

“For me, all closure means is the perpetrator's been caught, been dealt with. There's no closure, there's an aftermath which continues and will carry on.”

The most recent officer to die on duty was PC Sahib Lalli, who was taken to hospital after falling ill during a night shift in Trafalgar Square in November last year.

He was 38 years old and his wife gave birth to their first child the following month.

Sadiq Khan said: "Every single day our brave and dedicated police officers put themselves in danger, out on the capital’s streets, to keep us safe.

"As mayor I am incredibly proud and I believe that as Londoners we are tremendously privileged to have such a committed police service working so tirelessly to protect us.

"Today is about paying tribute to those men and women who have paid the ultimate sacrifice in the line of duty.

"We will always be indebted to them and they will not be forgotten."

The Met Commissioner said 2016 was a year of “tragic anniversaries” and highlighted how 23 years ago to the day PC Patrick Dunne was shot dead while investigating gunfire in Clapham.

It is also 50 years since Detective Sergeant Christopher Head, Detective Constable David Wombwell and PC Geoffrey Fox were fatally shot when they stopped three occupants of a car in Shepherd's Bush in August 1966.

One of the oldest anniversaries was the 100 years since the death of Detective Sergeant Matthew McLoughlin - the only protection officer to be killed on duty.

At the time of his death he was serving with Lord Kitchener in France but had been a protection officer to King Edward VII and George V.

A book of remembrance, dedicated in 2001 by the Queen, was available for family members and all other guests to view during an afternoon reception in the newly opened Simpson Hall.