A 13-year-old boy has been arrested on suspicion of sharing Islamist terrorist material.
The teenager was held in west London on Tuesday by officers from the Metropolitan police’s counter-terrorism command (CTC) before being released on bail until mid-June.
He was arrested on suspicion of the dissemination of terrorist material and his home was searched.
The arrest comes during growing concern about the radicalisation of young people.
The head of the CTC, Richard Smith, said: “While it is still very rare for such a young person to be arrested for a terrorism offence, in recent times we have seen a worrying increase in the number of teenagers being drawn into terrorism.
“This particular investigation remains ongoing, but more broadly, we work closely with a whole range of partners to try to protect and divert young, vulnerable people away from extremism and terrorism.
“The public have an important part to play in this, and we would urge anyone who thinks a friend or relative is becoming radicalised or drawn into a path towards terrorism to act early. Please contact us so that we might be able to get that person the help they need.”
Police saw the number of terrorism arrests for all age groups except children fall during the pandemic, and in the year to March 2021, 13% of suspects arrested for terrorism offences were aged under 18, compared to 5% the previous year.
Authorities fear that the increase in time spent online while Covid-19 restrictions were in force left more children vulnerable to being radicalised.