UPDATE: A 17-year-old boy arrested on suspicion of a terrorism offence has been released on police bail.
Detectives from the Met Police Counter Terrorism Command arrested the boy from north London on suspicion of encouraging terrorism, contrary to section 1 of the Terrorism Act 2006, at approximately 05.35hrs yesterday, Wednesday, 17 April.
He was detained in custody at a south London police station under the Police and Criminal Evidence Act before being bailed to return to the station on a date in early May.
Detectives have completed a search of an address in north London.
Enquiries are ongoing.