Suspected Woolwich attacker Michael Adebolajo has been discharged from hospital and taken into police custody, Scotland Yard has said.
Mr Adebolajo, 28, has been taken into custody at a south London police station, where he will be questioned.
The other suspect in the murder of Drummer Lee Rigby in Woolwich, Michael Adebowale, 22, was released from hospital earlier this week.
He appeared before Westminster magistrates court on Thursday. He is due to appear again at the Old Bailey on Monday.
Both men were shot by police in the wake of the death last Wednesday.
Police have also arrested two men aged 42 and 46 on suspicion of being involved in the illegal supply of firearms.