The younger brother of the Manchester Arena bomber Salman Abedi is "just as guilty of the murder of 22 people" as his brother, a court has heard.
Hashem Abedi, 22, is on trial at the Old Bailey accused of helping his brother plan the suicide attack.
Opening the case, prosecutor Duncan Penny QC said: "On the evening of Monday 22 May 2017 in the public foyer outside one of the entrances to the Manchester Arena in central Manchester shortly after the conclusion of a concert by the singer Ariana Grande, this defendant's brother detonated a large home-made improvised explosive device - a bomb packed with shrapnel contained in a rucksack on his back.
"The effects of the resulting explosion were both sudden and lethal.
"Twenty two people, men, women, teenagers and a child, were killed.
"Twenty eight people were very seriously injured, a further 63 people were seriously injured, 111 others were also hospitalised.
"The prosecution's case is that this defendant is just as guilty of the murder of the 22 people killed as was his brother.
"He is equally guilty of the attempted murder of many others and in doing so he was guilty of agreeing with his brother to cause an explosion or explosions of a nature likely to endanger life."
The authorities say nearly 1,000 people were injured in the attack
Salman Abedi detonated an explosive device as music fans left an Ariana Grande concert in Manchester Arena in 2017, killing 22 people and injuring 237 more.
Some 670 people have since reported they are suffering from psychological trauma as a result.
Alex Dibble, TalkRADIO Reporter said: "In the months before the attack, the two of them together conspired and planned it to the extent that they bought addresses in other parts of Manchester where they could store and experiment on prototypes of the bomb they were making.
“They bought a car to store equipment and chemicals that they were ordering which included screws and nails designed to inflict as much harm as possible when Salman Abedi eventually used it in his backpack and detonated it at the Manchester arena.
"The law means that even though Hashem Abedi was not the one who carried out the attack on 22 May, he is just as responsible, just as guilty as if he had done."
The court heard Manchester Arena was one of the largest in Europe with a capacity of some 21,000 people.
Hashem Abedi, originally from Manchester, denies 22 counts of murder, attempted murder and conspiring with his brother to cause explosions.
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