Manchester mass murderer built his own bomb?

Telegraph:

The Manchester suicide bomber may have built a second device which is now in the hands of fellow jihadists, police fear.

Officers who raided the home of Salman Abedi discovered a working bomb factory with a huge stash of explosive chemicals and other components.

Security sources now believe that Abedi assembled the bomb himself after learning his trade in Libya.

But the amount of material in his home has led to fears that he could have built more than one device and and distributed them to other British-based extremists.

A security source told the Telegraph: "The worry is there was enough to build two or three bombs and we can't rule that out."

Abedi arrived back in Manchester from Libya on Thursday, travelling via Istanbul and Dusseldorf.

The following day he visited the Arndale shopping centre in Manchester, where he was caught on CCTV buying a Karrimor rucksack.

It is believed he then spent the weekend putting together the main components of the device, including the detonator.

On Monday he then travelled the three miles from his home in Elsmore Road in the Fallowfield district to a rented apartment in Granby Row on the edge of Manchester's Gay Village.

The building was raided by special forces at lunchtime on Wednesday and specialist forensics teams and bomb squad operatives were still at the building on Thursday.

Sources believe Abedi may have used the £75 a night apartment to put all the components of the device together, before heading off late on Monday evening to make his way to the Manchester Arena where he killed 22 people.

The use of two addresses to assemble the device was a tactic used by the 7/7 bombers who also spent months learning how to build a bomb at a training camp in Pakistan.
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Police believe he learned to assemble the bomb or bombs on his trips to Lybia and possible Syria.  It is somewhat unusual for terrorist organizations to combine the function of assembling a bomb and exploding it.  They prefer to have the bomb maker provide numerous bombs to potential mass murderers.