Transcript for Authorities found bomb-making workshop in Salman Abedi's home

Now to new arrests in connection with that concert terror attack. Authorities detaining more suspects in Britain and taking the bomber's father and brother into custody in Libya where they learned new details about the bomber's path to ISIS. Brian Ross is here with more. Good morning. Reporter: Good morning. Major developments overnight with important new details about the bomb and the bomber and his planning provided in a confession by the bomber's younger brother. Officials this morning say the bomber's home in Manchester where they blew open the door was a kind of bomb workshop. There are no signs of that now through the open front door of the abandoned house but officials say they discovered a huge load of unused chemicals, more than enough for several more bombs. And we are learning more this morning about Salman Abedi's rapid road to jihad. A secret life beyond the front page pictures of a British schoolboy and a goofy-looking teenager at the beach. His decision to become part of ISIS came two years ago. That's according to the reported confession of his younger brother Hashim arrested Wednesday by police in Libya supposedly about to carry out his own terror attack. Authorities say Hashim told them that he and his brother began watching ISIS online videos in 2015, closely studying a range of videos on how to build suicide bombs. Experts say the details seen in the pictures of the Manchester bomb obtained by "The New York Times" show greater physical kitation including a design used by ISIS in Paris and Brussels and more than one detonator. Really suggesting that he probably did not act alone, that he probably had some help, that he certainly had some advice on how to create the bomb. Reporter: Five weeks before the attack, the two brothers traveled to Libya an ISIS stronghold and the family's ancestral home. With Salman returning to Manchester on may 17th. Just five days before he would go to the concert arena. Oh, my god. Reporter: And then set off his bomb. Police in Manchester have now arrested seven other people in the case including another of the bomber's brothers and his father is under arrest in Libya as authorities continue to pursue what they call a network of terrorists, robin. We've learned that British authorities will no longer share information about this attack with their U.S. Counterparts. That's right. They're furious. The crime scene photos ended up in "The New York Times" blaming American authorities for the leaks. I covered a lot of these stories around the world. In most cases the British legal system proves to be the least forthcoming with details that other countries see as the public's right to know. Thanks very much.

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