A Metropolitan Police officer arrested in connection with the disappearance of Sarah Everard was “not on duty” when she went missing.
Assistant Commissioner Nick Ephgrave described the arrest as a “serious and significant” development in the search for the 33-year-old.
Speaking to reporters outside Scotland Yard on Wednesday, a week on since Ms Everard was last seen or heard from, he said: “Our inquiries suggest that this officer was not on duty at the time of Sarah’s disappearance.”
Asked if he believed she might still be alive, the officer replied: “We are searching as hard as we can to find Sarah so we really hope that is the case, of course.”
He said the fact a serving police officer had been detained was both “shocking and deeply disturbing”, and the force was working at “speed” to find Ms Everard.
Scotland Yard appealed again for the public’s help, with Mr Ephgrave saying “every piece of information is important to us”.
An extensive search involving police, relatives and volunteers has been under way to find the marketing executive who disappeared after leaving a friend’s house in Clapham, southwest London, at about 9pm last Wednesday (3 March).
Ms Everard went missing while walking to her home in nearby Brixton – a journey that was expected to take her around 50 minutes. She has not been seen or heard from since.
She is described as 5ft 4in (162cm) tall with a slim build and blonde hair.
Ms Everard was wearing a green rain jacket, navy blue trousers with a white diamond pattern, and turquoise and orange trainers – and is thought to have been wearing green earphones and a white beanie hat too.
Her family described her disappearance as being “totally out of character” and said her phone was not ringing and WhatsApp messages were not getting through.
Last night, a serving Metropolitan Police officer was arrested at an address in Kent in connection with her disappearance.
A woman was arrested at the same address on suspicion of assisting an offender.
Both remain in custody at a London police station.
On Tuesday two new photographs of Ms Everard were released by police.
One of the new images showed her wearing the same coat as on the night she went missing.
The image, a CCTV still taken from a doorbell camera, showed Ms Everard walking along the A205 Poynders Road at about 9.30pm.
The footage captured her walking alone from the junction at Cavendish Road, toward Tulse Hill, which lies south of Brixton.
The image appears to suggest she walked through Clapham Common and was heading towards her home, although police have said it is unclear if she made it there.