The number of children arrested for <a href="https://www.thenationalnews.com/world/three-bomb-plots-foiled-but-number-of-uk-teenagers-arrested-for-terrorist-offences-rises-1.1178300">offences linked to terrorism</a> increased last year in Britain amid growing concerns about online grooming during the Covid-19 pandemic. Under-18s were the only age group to buck the trend of decreasing arrests in the year to March 2021 as national restrictions on movement affected planning and limited large gatherings previously targeted by extremists. British police arrested 166 people for terrorism-related offences to March 2021, a reduction of 37 per cent on the previous 12-month period. Arrests of under-18s, which increased from 9 to 21, made up 13 per cent of the total. Senior counterterrorism officers said extremist groups were exploiting the pandemic to target children during lockdowns as they spent more time in front of computer screens at home. The UN’s counterterrorism committee said this year that some groups were using online games to try to secure new recruits. Britain's most senior counterterrorism officer, <a href="https://www.thenationalnews.com/world/uk-counter-terrorism-chief-says-online-extremism-cannot-be-policed-as-covid-provides-perfect-storm-1.1142642">Neil Basu</a>, told MPs last year that children as young as 13 were starting to talk about committing terrorist acts. Mr Basu said he was especially worried about grooming by the far-right, although he said ideology could be ambiguous and sometimes perpetrators were only "interested in violence". Latest UK government statistics showed a link between periods of lockdown and reduced levels of arrests for most age groups. During the first period of national lockdown in England and Wales, only 31 terrorist-related arrests were made from April to June 2020. The number increased as restrictions were eased only to fall again during the third national lockdown from January to March this year. The number of people being stopped at Britain’s borders because of terrorist-linked suspicions fell to unprecedentedly low levels. The statistics showed the number of such arrests by nationality in the UK in the 20 years since the 2001 terrorist attacks on the US. The highest non-British group were from Algeria with 194 arrests, followed by Iraqis, 175, and people from Pakistan, 170. The majority, nearly 3,000, were Britons or British dual-citizens.