More than 400 exhibits, samples and items have been recovered by police investigating the Amesbury novichok poisoning, with officers warning searches could last months.

Also on Saturday, the army was seen removing an ambulance that was used in the treatment of Dawn Sturgess and Charlie Rowley when they first fell ill.

Officers have been looking for other possible sites or sources of contamination, as well as gather further evidence, as part of a "painstaking" investigation.

Image: Flowers for Dawn Sturgess, who died after being exposed to novichok

Ms Sturgess, 44, died a week ago after she apparently handled a bottle contaminated with the nerve agent in Amesbury, Wiltshire.

Her partner Mr Rowley, 45, remains in hospital where he is in a serious but stable condition.


Their exposure comes after ex-Russian spy Sergei Skripal and his daughter Yulia were poisoned with the same substance in Salisbury in March.

They recovered after many weeks in hospital.

Image: Large parts of Amesbury remain off limits as the investigation continues

Assistant Commissioner Neil Basu, head of counter terrorism policing in the UK, said: "It is not an exaggeration to say that the search process linked with both this and the Salisbury investigation has been one of the most complex and difficult that UK policing has ever faced.

"Not only are we trying to solve an extremely serious crime that has been committed, but we're also working to identify any potential outstanding risks to the public; all whilst ensuring that all those involved in the search process are not themselves exposed to any risk of contamination.

"It is painstaking and vital work, which unfortunately takes a very long time to complete, but I am sure that the public understands why it is absolutely necessary."

How does novichok affect the body?

Meanwhile, Ms Sturgess's friends are planning their own memorial for her on Friday afternoon which is "open to anyone and everyone".

Ryan Knight, who knew Ms Sturgess through their time at the Salisbury homeless shelter John Baker House, said he did not want to "disgrace" his friend's funeral.

He told Sky News: "I prefer not to turn up rather than get dirty looks.

"I'll be in the background.

"When her immediate family go, I'll go over and pay my respects."

Image: A memorial is being planned by the friends of Dawn Sturgess

Mr Knight described Ms Sturgess, who had three children, as having " lots of friends", adding that the manner of her death was "something which is never expected".

"These are two innocent people."

Image: Ryan Knight was a friend of Dawn Sturgess

It is not yet clear where the contaminated bottle came from and how it came to be in Mr Rowley's home, where it was found.

But scientists at the Defence, Science and Technology Laboratory at Porton Down are testing it to confirm whether Ms Sturgess and her partner were affected by the same batch of novichok that poisoned the Skripals.

Ms Sturgess's post mortem examination is scheduled to take place on Tuesday and an inquest into her death is set to open in Salisbury on Thursday.