UK police have arrested four men on suspicion of terrorism offences.
The men all in their 30s are from Luton. They were arrested on suspicion of being involved in preparation of act of terrorism.
The men are now held at a London police station. Police is now searching other ares in Luton.
Police said the arrests are not connected to last month’s attacks in Paris.
Media reports described the arrest as “quite significant”.
The arrests were carried out in a joint operation by the Metropolitan Police’s Counter Terrorism Command and the Eastern Counter Terrorism and Intelligence Unit.