- Video report by ITV News Correspondent Sally Lockwood
A teenager has appeared in court charged over the Parsons Green Tube attack.
Ahmed Hassan, aged 18, of Cavendish Road in Sunbury, Surrey, has been charged with attempted murder and causing an explosion with intent to endanger life.
He is accused of buying parts to make an improvised explosive, before leaving it on a packed District Line Tube train at Putney Bridge.
A 17-year-old also held in the aftermath of last Friday's attack in west London has been released from custody with no further action, police said.
Thirty people were injured when the home-made bomb caused a fireball on the packed morning train last Friday.
Hassan, an Iraqi asylum seeker, was detained in Dover just over 24 hours after the attack.
Hassan appeared at Westminster Magistrates Court on Friday, wearing a grey jumper.
In a statement, Scotland Yard said Hassan would be facing a charge of using a chemical compound known as TATP to cause an explosion with intent.
He also stands accused of trying to "murder persons travelling on a District Line Train from Wimbledon", the Met said.
Hospitals across London treated several people for burn injuries following the incident, which left Parsons Green station closed for a number of hours.
Searches are continuing at one address in Surrey and two in Newport, Wales.