30 passengers were injured in the attack last Friday
A teenager has been charged in connection with the Parsons Green London Underground terror attack last Friday.
Ahmed Hassan, 18, of Sunbury, Surrey will appear at Westminster Magistrates Court.
He has been charged with attempting to murder people travelling on a District Line train and possessing explosives.
He also face a charge of using the chemical compound triacetone triperoxide - known as TATP - to cause an explosion likely to endanger life.
No-one was killed when the crude home-made bomb failed to properly detonate, but 30 passengers were injured.
Hassan was arrested in Dover, Kent on Saturday morning, on suspicion of planting the device.
He is believed to have spent time in the care of Penelope and Ronald Jones, from Sunbury-on-Thames, who received MBEs for services to children and families in 2010.
The Joneses have been highly respected foster parents for almost 40 years and looked after up to 300 children, including eight refugees.
Three other men, aged 25, 30 and 17 remain in custody in connection with the attack.
Two men, aged 21 and 48 have both been released from custody without charge.
Yahyah Farroukh, 21, was detained at a fried chicken shop in Hounslow, west London, on Saturday.
Like Hassan, Mr Farroukh is also understood to have spent time in the care of Mr and Mrs Jones.
The 48-year-old man is also understood to have been arrested at the Newport "halfway house".
The head of the Met Police's Counter Terrorism Command, Dean Haydon, has called the investigation "fast-moving", adding: "A significant amount of activity has taken place since the attack."
Police are still searching one address in Surrey and two in Newport, Wales in connection with the attack.