British authorities have arrested a 10th person in connection with the murder of soldier Lee Rigby in Woolwich.
The 50-year-old man was arrested in Welling, south-east London, on suspicion of conspiracy to commit murder.
Police also confirmed an address in south-east London was being searched.
Meanwhile shadow home secretary Yvette Cooper said ministers must put “more effort” into fighting the “murderous narrative” of hate preachers.
Four of those arrested have been bailed, two released without charge and four remain in custody over the killing on Wednesday.
Two suspects, Michael Adebolajo, 28, and Michael Adebowale, 22 – both Britons of Nigerian descent who are understood to be converts to Islam – remain in custody in hospital in a stable condition after being shot and wounded by police at the scene after the killing.
The Metropolitan Police said the men would not be questioned until they had been discharged from hospital, and the time they had spent under arrest so far would not count towards the maximum amount of time they could legally be held without charge.
Questions are still being raised over what British authorities knew about the suspects before the killing.