A teenager is accused of buying the Parsons Green bomb from Amazon and filling it with knives and shrapnel with the intention of murdering dozens of rush hour commuters.
Ahmed Hassan, 18, allegedly placed a bomb hidden in a Lidl bag and covered it with a pair of trousers on a District Line train and departed the train at Putney Bridge prior to the device detonating.
He appeared at Westminster Magistrates' Court on Friday charged with attempting to murder a Tube full of commuters and schoolchildren and of using a chemical compound known as TATP to cause an explosion likely to endanger life.
The explosion, described by passengers as "a fireball", still left 30 people injured. Officers have said the device would have killed dozens of people had it properly activated.
Prosecutor Lee Ingham said it is the prosecutions case Mr Hassan bought the components of the home-made bomb from Amazon.
"There were many hundreds of grams of TATP in the device, an electronic timer and several containers of quantities of metal shrapnel including knives, screws and similar items clearly designed to cause severe injuries and death to those nearby.
"The device did not function as intended. It did not function the TATP, probably due to inaccurate construction."
Mr Hassan spoke only to confirm his name and address. Deputy chief magistrate Tan Ikram has sent his case to be heard at the Old Bailey on October 13.
The device that failed to fully detonate on the District Line train at Parsons
Mr Hassan, of Sunbury, Surrey, appeared in court on Friday afternoon. He was arrested in Dover, Kent, on Saturday after police circulated his picture and he was arrested.
Hassan's court appearance came amid claims that the mother of a Syrian refugee who was held over the bombing but then released had suffered a heart attack after hearing of her son's arrest.
Yahyah Farroukh, 21, who was was released without charge on Thursday, was seized by police last weekend outside Aladdins Fried Chicken, in Hounslow, west London, where he worked.
His boss at the takeaway, Suleman Sarwar, demanded an apology from the police and said his mother was in a critical condition in a hospital in Egypt after collapsing from shock.
Mr Sarwar said the takeaway had received "abuse, threats, anger, and hatred" after Mr Farroukh was labelled "a terrorist to the world".
