Twelve people arrested in connection with the Westminster terror attack have all been released without charge.
A 30-year-old man detained on 26 March in Birmingham on suspicion of preparation of terrorist attacks was released on Saturday, Scotland Yard said.
He was arrested four days after Khalid Masood's murderous assault, which left four dead, including police constable Keith Palmer outside the Palace of Westminster.
Eleven other people previously held in connection with the investigation have also been released without further action, police said.
Inquests into the deaths of both Masood, 52, who was shot dead by armed police after his knife attack on PC Palmer, and his victims, were opened and adjourned at Westminster Coroner's Court this week.
Coroner's officer Eric Sword said the provisional cause of death of Masood was "a gunshot wound to the chest".
He said Masood, who was also known as Adrian Elms and Adrian Ajao, was identified by fingerprints and DNA.
The inquest heard before he died, Masood drove his hire car across Westminster Bridge and mounted the pavement twice "in an apparently deliberate attempt to target pedestrians".
Pre-inquest reviews for PC Palmer and Masood are expected to be heard at the Royal Courts of Justice on 19 May.
The other victims killed were American tourist Kurt Cochran, 54, retired window cleaner Leslie Rhodes, 75, and college administrator Aysha Frade, 43.
More than 35 others were injured, including three police officers. Seven victims remain in hospital.