Third arrest over mustard gas find in Roughton Moor Woods
A third person has been arrested on suspicion of being in possession of a noxious substance after mustard gas canisters were found in Lincolnshire.
The canisters were found at Roughton Moor Woods near Woodhall Spa on Sunday, and dealt with by bomb disposal teams.
Lincolnshire Police said it was searching a property in the village.
A 38-year-old man from Lincoln was arrested on Tuesday and a woman was arrested on Wednesday. Both remain in police custody.
A Royal Navy bomb disposal team is currently searching the site of a lake at nearby Stixwould.
Supt Phil Vickers, of Lincolnshire Police, said: "It's likely we will continue to investigate the site at Stixwould for the rest of the day and into tomorrow.
"We're taking a cautious approach and not ruling out any possibilities."
An earlier search of a property on Longdales Road, Lincoln, found no noxious substances, police said.
Police said the devices were uncovered by people digging for bottles in the woods.
Work was continuing to confirm the woodland was safe and not a risk to people who visit the area, the force added.
The National Police Air Service is currently assisting at the scene.
The former RAF Woodhall Spa base was located in the area from 1942 until it closed in the mid 1960s. There was also an army camp near where the canisters were found.
A spokesperson for the MoD said it continued to support the operation and police investigation but it is yet to comment on how the canisters may have come to be on the site.
Police believe they may have been in situ since it was an operational base.
The canisters were taken to the Defence Science and Technology Laboratory at Porton Down, Wiltshire.
The find comes almost 20 years after The Independent revealed that more than 60 military sites were contaminated by mustard gas, despite being declared "safe" by the Ministry of Defence (MoD).
Mustard gas was used during World War One. It was outlawed by the Geneva Protocol of 1925.