Police have arrested a 31-year-old man from Norfolk on suspicion of raising funds for terrorism.
Detectives from the Met Police's Counter Terrorism Command made the arrest at around 6.10am on Thursday morning.
The man was also detained on suspicion for encouraging support for a banned terror group.
Norfolk police said the arrest was carried out on the eastern coast of the county, but would not give an exact location.
He is currently in custody at a central London police station, the Met said and he may be bailed later today.
Searches were carried out at two addresses in Norfolk and one in north London.
The arrest relates to suspected activities overseas, police said.
A spokesman for Norfolk Police said the force was 'aware' of the arrest, but added it did not have 'much involvement'.
A spokesman for the Met Police would not reveal where the arrest was made and added it was not directly related to ISIS.
The spokesman added the man was expected to be bailed later today.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here