The Prime Minister has said he was “shocked and deeply saddened” after human remains were discovered in the search for Sarah Everard.

A serving Metropolitan Police officer, who is in his 40s, is being questioned on suspicion of the 33-year-old’s kidnap and murder.

Met Commissioner Dame Cressida Dick said on Wednesday night that remains had been found in an area of woodland in Ashford in Kent by detectives investigating Ms Everard’s disappearance.

Boris Johnson said on Thursday: “I am shocked and deeply saddened by the developments in the Sarah Everard investigation.

“Like the whole country, my thoughts are with her family and friends. We must work fast to find all the answers to this horrifying crime.”

The officer, who is in the Parliamentary and Diplomatic Protection Command, was held on Tuesday night on suspicion of kidnap before being further arrested on suspicion of murder and a separate allegation of indecent exposure the following day.

On the day of Ms Everard’s disappearance, he was reportedly working a 2pm to 8pm relief shift at the US Embassy in Nine Elms, south-west London, around three miles from where she was last seen.

According to unconfirmed reports, detectives are investigating whether he might have used his warrant card to entice Ms Everard towards his car before snatching her.

Home Secretary Priti Patel said “every woman should feel safe to walk our streets without fear of harassment or violence”, after Dame Cressida sought to reassure the public.

Sarah Everard missing
A police cordon in Fridd Lane near an area of woodland in Ashford in Kent (Gareth Fuller/PA)

“It is thankfully incredibly rare for a woman to be abducted from our streets,” Dame Cressida said.

“But I completely understand that, despite this, women in London and the wider public – particularly those in the area where Sarah went missing – will be worried and may well be feeling scared.”

The Met said the arrested officer’s main job was uniformed patrol of diplomatic premises, but would not specify where he had worked. He was not on duty at the time of Ms Everard’s disappearance.

The diplomatic protection squad is responsible for guarding the Parliamentary estate, including Downing Street and the Palace of Westminster, as well as embassies in London.

A woman in her 30s has been arrested on suspicion of assisting an offender.

In a statement, Dame Cressida said: “The news today that it was a Metropolitan Police officer arrested on suspicion of Sarah’s murder has sent waves of shock and anger through the public and through the whole of the Met.

Sarah Everard
A missing sign outside Poynders Court on the A205 in Clapham (Victoria Jones/PA)

“I speak on behalf of all my colleagues in the Met when I say we are utterly appalled at this dreadful news. Our job is to patrol the streets and to protect people.”

Investigators are continuing to work “around the clock” on what Dame Cressida described as a “very fast moving” case.

The remains have not yet been identified and it could take some time to do so, the Commissioner added.

She said people living around the Clapham and Tulse Hill areas of south London could expect to see increased patrols in the area.

As well as the search of the woodland in Ashford, over the course of Wednesday, officers also searched a property in Deal, Kent.

Multiple cars were taken away by investigators and a neighbour told the PA news agency a police officer lived at the address with his wife and two children.

Marketing executive Ms Everard vanished while walking home from a friend’s flat in south London on Wednesday March 3.

Ms Everard is thought to have walked through Clapham Common towards her house in Brixton – a journey which should have taken around 50 minutes.

She was last captured on a doorbell camera walking along the A205 Poynders Road towards Tulse Hill at around 9.30pm on March 3.

A vigil titled “Reclaim these streets” has been organised on Facebook and is due to take place at Clapham Common bandstand at 6pm on Saturday.

Organisers said: “It’s wrong that the response to violence against women requires women to behave differently. In Clapham, police told women not to go out at night this week. Women are not the problem.

“We’ve all been following the tragic case of Sarah Everard over the last week. This is a vigil for Sarah, but also for all women who feel unsafe, who go missing from our streets and who face violence every day.”