Boris Johnson raises UK terror threat level to severe. Government sources say this should not be taken as an indication of any further specific live threat. #UK #Liverpool #TheGuardian #TheSun

A fourth 20-year-old man was arrested in addition to the three men aged 18, 26, and 29 arrested on Sunday. They are all being interviewed by police today. 

Police believe they know the identity of the deceased passenger but have not yet revealed it. They think he built the explosive device in the taxi, but they are uncertain as to a motive or why the Liverpool Women’s hospital was chosen. 

The arrested men are believed to be “associates” of the taxi passenger. 

The UK terrorism threat level was increased to severe, meaning an attack is “highly likely”. Government sources say this should not be taken as an indication of any further specific live threat. 

The taxi driver was named as David Perry. He has now been released from hospital. His wife, Rachel Perry, said he is “doing OK but is extremely sore”. 

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