FBI warned Britain about Manchester mass murderer

Daily Mail:

UK security chiefs were warned in January that Salman Abedi was planning an attack in Britain, it was claimed last night.

According to a security source, the FBI told MI5 that Abedi was part of a North African Islamic State cell plotting to strike a political target in the UK.

The information came from a US investigation into Abedi and his links to terrorist groups in Libya. The Mail on Sunday has also been told that US security services put him on a terror watch list – used by agents to identify key suspects – in 2016.

The shocking claim piles further pressure on MI5 to reveal when and how it became aware of Abedi, and why UK spies decided he did not pose a significant threat to British security.
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It would appear that US intelligence was also responsible for finding many of his associates in Libya.  It makes the UK's upset about the release of bomber's name all the more curious since the FBI knew about who he is before the police started the roundup.