The alleged Manchester Arena plotter accused left his fingerprints on packs of nails in a car allegedly used to store the bomb-making kit, a court has heard.
Hashem Abedi, 22, is accused of helping his brother Salman plan the May 2017 attack, including gathering chemicals for homemade TATP explosives.
His fingerprints were found at a flat in Somerton Court, Blackley, north Manchester, allegedly used to stockpile the ingredients to make the bomb, the Old Bailey heard.
They were also identified at a terraced house at Lindum Street, Rusholme, used as a delivery address for the chemicals bought online via Amazon, jurors were told.
When the brothers went to visit family in Libya, the bomb-making kit was allegedly left in a parked Nissan Micra car.
Salman returned to the UK alone just days before the attack and assembled the deadly device packed with shrapnel at a rented flat in Granby Row, it is alleged.
Following the suicide attack which claimed 22 lives, police recovered the Micra and examined it.
Fingerprint expert Philip Balduini told the court that both brothers’ prints were in the car, which allegedly contained traces of TATP.
Hashem’s prints were on items including a cardboard box, two plastic bottles inside a holdall and a large blue drum, he said.
Inside the blue drum were seven packs of assorted nails, also with Hashem’s prints on them, jurors were told.
The defendant, from Manchester, has denied 22 counts of murder, attempted murder and conspiracy to cause explosions.
Mr Justice Baker adjourned the Old Bailey trial until Monday.