6:31 AM PT -- The suspected bomber has been identified as 22-year-old Salman Ramadan Abedi.
Greater Manchester Police say they arrested the 23-year-old man Tuesday. They have not said what his connection is to the bomber, who was one of the 22 killed when he detonated the "nail bomb" Monday night in the rotunda at Manchester Arena.
The bust seems to point to the bomber not acting as a so-called lone wolf.
ISIS has claimed responsibility for the attack, claiming it was executed by one of its "soldiers."
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