Counter terrorism detectives arrested two men in London on suspicion of “preparation of terrorist acts”, following a raid in west London.
The men, aged 19 and 20, are thought to be involved in a plot to attack Britain but police have refused to comment on further details regarding the intended target.
The 19-year-old was arrested on suspicion of preparing terrorist acts, and the 20-year-old on suspicion of funding terrorism, failure to disclose information regarding a terrorist act and suspicion of preparing terrorist acts under a separate investigation by the South East Counter Terrorism Unit.
A number of addresses in west and south west London were also searched by specialist officers, but police have made no further comment.
A third man, aged 19, has also been arrested in south-east London on suspicion of a religiously aggravated offence in relation to a separate matter.
All three men remain in police custody as inquiries are ongoing.
The news comes as the Commissioner of the Metropolitan Police warned an attack on the UK was a matter of “when, not if”. The current terrorist threat level is considered to be severe; meaning an attack in Britain is likely.