Four people have been arrested by police on suspicion of being concerned in the commission, preparation or instigation of acts of terrorism in Syria
Two men aged 29 and 18 both from Levenshulme, and a 21-year-old woman from Trafford are in custody, Greater Manchester Police said.
A 29-year-old man from Oxford has been arrested by the South East Counter Terrorism Unit on suspicion of the same offence.
Police said a number of properties were now being searched as part of the investigation.
More top news
Declan Donnelly will host the show alone when the show returns on March 31 following his partner Ant McPartlin's return to rehab, ITV says.
Police say they are reviewing 'malicious comments' on social media following the news of the death of two-year-old Kiara Moore.
There will be a new element of performance assessment before pay rises are awarded, writes Political Editor Robert Peston