Ms Lord has not been seen since last Friday, with police believing she entered the water at the River Wensum after her clothes and personal belongings were found nearby, with her coat seen on the water.

The 55-year-old disappeared after leaving work early in Norwich city centre - with police describing her actions as "out of character".

In a news conference at the scene on Thursday, Chief Superintendent Dave Buckley said officers had not been able to establish her state of mind on the day she went missing.

He said that "everything we know is pointing to a high probability that Gaynor went into the water", but added: "Nobody's seen her go into the river."

A friend of Ms Lord told Sky News she missed a phone call from her just minutes before he last sighting on CCTV.

Two calls to Julie Butcher were timed at around 2.37pm - a few minutes before she left work early - and then again at 4.15pm on Friday 8 December, after the last CCTV sighting of her.

"I answered the call and said 'who is it?' and she said 'it's Gaynor'," Ms Butcher said of the first call.

"Then my phone rang and it was one of my clients, so I said to Gaynor can I call you back and she said 'yes'.

"I rang her back and then she didn't answer, so I called her again and left a message, and then I messaged her on WhatsApp."

Ms Butcher described the second call from Ms Lord as a "pocket call".

"It sounded like she was walking along," she said.

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Police have given the following timeline of Mrs Lord's movements:

2.44pm: Mrs Lord, who is described as white, 5ft 6in tall, and has a blonde shoulder-length bob, is working at the Bullards Gin counter in the basement at Jarrolds department store - she is clearly visible in a CCTV image

2.45 - 2.46pm: She leaves via the loading bay on Bedford Street

2.47pm: Mrs Lord walks onto London Street past the Cosy Club

2.48pm: She makes her way to Queens Street, without waiting for a red light and narrowly misses moving traffic before walking towards the cathedral

3.22pm: CCTV shows her in The Close at the cathedral entrance - shortly before exiting through the archway, as she puts on her olive-coloured coat

3.23pm: Mrs Lord walks away from the cathedral on Queens Street. CCTV shows a clear image of the coat she was wearing

3.49pm: CCTV captures her walking along St George's Street near the Playhouse theatre

3.53pm: Walks along St Crispins Road towards Pitt Street

4.01pm: Mrs Lord walks up St Augustines Street - her final movements captured on CCTV before she went missing.

Police keen to learn lessons from Bulley case

Police are keen to hear from anyone who saw Mrs Lord between 2.50pm and 3.23pm - because it was "not clear where she goes inside the cathedral grounds during this time".

Some 30 people have already come forward with information in relation to the disappearance.

Ch Supt Buckley also confirmed that his officers were in direct contact with Lancashire Police - who led the search for Nicola Bulley at the start of the year.

"In terms of Lancashire, we've reached out to them and to investigators that worked on that case," he said.

In further cross-service collaboration, he said a specialist team from Lincolnshire was also assisting in the search.

No marks were found on the grass by the river to indicate that someone had gone in the water, Norfolk Police confirmed.

The force said specialist divers were working in an "extraordinarily challenging environment" and warned it could take "a couple of days" or longer to complete the search of the stretch of river.