Anti-terror police have raided properties in London and Stoke and arrested two men in Britain's capital city.
A 33-year-old and a 40-year-old man were held under new anti-terror laws after being arrested at separate addresses in south-east London.
One home in Stoke was searched by anti-terror officers in connection with the inquiry, along with four in the capital city.
Police held one man on suspicion of preparing acts of terrorism and the other for possessing suspected fraudulent documents.
They were held as part of an ongoing operation, which saw a string of arrests earlier this month and in late November.
A total of six people were detained. One 37-year-old man has been charged.
A Scotland Yard spokesman said: "Searches are taking place at five residential addresses."
More information to follow. For more updates, check out IBTimes UK.