The man, aged 45-years-old, was arrested in the Belfast area under Section 41 of the Terrorism Act.
He is currently being taken to Musgrave Serious Crime Suite to be questioned by detectives.
Eight men aged 72, 57, 47, 45, 43, 33 & 22 years old were also arrested in connection with the attempted murder.
All eight men have been released following questioning.
A 25 year old man who was arrested in connection with the claim of responsibility made following the attempted murder of DCI Caldwell has been released following questioning.
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