Transcript for Hunt for possible accomplices in Manchester bombing

Next tonight to that deadly suicide bombing in Manchester, the concert with American pop star Marco Rubi Reariana grande. Was he scouting the mall ABC's Terry Moran. This new image tonight in retrospect so sinister. Salman Abedi taking out the garbage cans at his suburban home, wearing a traditional hooded north African robe and sandals. And today, these haunting security camera images of Abedi, at a shopping mall just three days before the attack, baseball cap pulled down, apparently carrying the same backpack he used in the bombing. He spent his final night here, in a rented apartment just two miles from the arena, phoning his mother in Libya to say, "Forgive me." Today, more police raids across the region, and in the town of wigan, clearing the neighborhood after bomb technicians moved in. Police desperately trying to unraffle a terror network. They call this the "Curry mile" in Manchester. It's the heart of the Muslim community here and a very welcoming place, but within two miles ofot, and the surrounding neighborhoods, 16 young men over the past couple of years have committed acts of terrorism. But the people here say Abedi and the others don't represent them. Terry Moran with us live from Manchester. Police today have found several key pieces of evidence in those raids? Reporter: To that's right, authorities say the police investigation is hitting paydirt, important evidence, suspicious items today, significant arrests, four men charged with terrorism offenses tonight. Investigators are rolling up a terror network they didn't know about.

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