Police are appealing for anyone who might have seen Mr Nicol to contact them.
Supt. David Byrne speaks to ITV News about the investigation.
More top news
The RMT Union has suspended a 24-hour rail strike planned for Tuesday 30 May, in light of the Manchester terror attack.
Police are investigating after a man wearing a balaclava and black tights over his head robbed a Gateshead takeaway.
The threat level has been raised to critical by MI5's Counter-Terrorism Analysis Centre.