Bored and isolated youngsters could be more susceptible to radicalisation and grooming as they spend longer online unsupervised during the coronavirus lockdown, police chiefs have warned.

Chief Superintendent Nik Adams, the Prevent programme’s national coordinator, said a small number of vulnerable people are at “greater risk of being drawn towards terrorist activity”.

Extremists... will look to exploit any opportunity to lead those people into harm, often using topical issues as hooks to lure them in

He said: “Isolation may exacerbate grievances that make people more vulnerable to radicalisation – such as financial insecurity or social alienation.

“The extremists and radicalisers know this and, as ever, will look to exploit any opportunity to lead those people into harm, often using topical issues as hooks to lure them in.”

Counter terror police fear the risk of radicalisation may increase for some vulnerable people as the pandemic sees young people spend more unsupervised time online and “feelings of boredom and isolation may be exploited by negative influences and online groomers of all kinds”.

Officers are also worried by a “significant” drop in the number of reports being made to the anti-terror Prevent programme in the wake of school closures and while other public services are stripped back amid the outbreak.

Teachers and health care workers are among those who refer individuals to the programme designed to identify those at risk of radicalisation by extremists – with referrals from those working in education typically accounting for more than 30% of annual totals.

I want parents to know that there is help and support available if someone in your household’s behaviour has changed and you are worried that they may be being groomed

Referrals have fallen by around 50% since the lockdown was announced, Mr Adams said.

He added: “Schools, mental health workers and other public services provide vital support and protection to young and vulnerable people and the combination of those services being affected by Covid-19 and the fact people are spending more time online means a small number of vulnerable people are at greater risk of being drawn towards terrorist activity.

“What concerns me greatly is that the decline in the number of referrals doesn’t mean that there are fewer people that need our help, but that fewer people are able to access the support they need.”

Despite the reduction in referrals, the threat to the UK from terrorism has not diminished, police warned as they turned to the public to ask for help in identifying warning signs and report concerns.

Mr Adams said: “As we all adapt to the prolonged lockdown, I want parents to know that there is help and support available if someone in your household’s behaviour has changed and you are worried that they may be being groomed.

“It’s vital that safeguarding remains at the heart of that support, so we can remain vigilant as a society and make sure the vulnerable people in our communities stay protected from those intent on doing them, and us, harm.”