POLICE have issued warnings over large numbers of children congregating and substantial quantities of an “extremely dangerous” gas being used ahead of lockdown measures being eased further.

North Yorkshire Police chief constable Lisa Winward has also outlined the scale of the challenge facing the force as lockdown restrictions have been lifted, saying it had seen a considerable increase in calls about antisocial behaviour, particularly at beauty spots.

She said the force was planning “a full policing operation” for the weekend, which will see a number of pubs reopening for the first time since March.

Ms Winward, who started her career with the force in 1993 as a special constable, said intelligence was being gathered by officers about how many pubs in the county would reopen from Sunday, and that it was considering how it could use “traditional legislation”, such as the Public Order Act, alongside the recent Covid-19 legislation, to deal with people acting unsafely.

Speaking during a public accountability session run by police, fire and crime commissioner Julia Mulligan, the chief constable said concerns were mounting over a huge amount of silver nitrous oxide canisters that had been used and discarded at beauty spots in recent weeks.

Medics have said inhaling the gas, also known as Whippits which gives feelings of euphoria, directly from the canister is very dangerous as it is under high pressure and can cause a spasm of the throat muscle and stop a person breathing.

Ms Winward said: “We have seen what we believe is quite a lot of young people using the little silver gas canisters. They are being found in a lot of fields. Please do not use these substances, we don’t really know the impact they can have on people’s health.”

She said the force was linking in with communities and the licensing authorities to try and make the easing of the lockdown as safe as possible “for those people who do want to go out and enjoy the fact that our pubs and restaurants are open”.

Ms Winward said it was clear people not reporting all antisocial behaviour, but urged residents to help police build a realistic picture of the situation in the county.

She added: “My urge would be please act responsibly.”

The force’s most senior officer also raised concerns over large groups of youngsters meeting in public areas and called on parents to help ensure their children were observing social responsibility.

She said: “I really appreciate children are off school and it is really difficult for parents to lock them indoors for all of the time as some home schooling is going on and some is not.

“We have been out to numerous incidents and taken children home to their parents. We’ve tried to use communications and social media to ask parents if they know where their children are and highlight the risks to their family if the infection is spread.”