There were long delays on both sides of the Wallasey Tunnel this afternoon (July 21).
Traffic approaching the tunnel was at a standstill after concerns for the safety of a man on a bridge nearby.
Police were called to Poulton Road near to the tunnel at 1.52pm and negotiators attended the scene where they talked to the man.
There was heavy traffic on major roads nearby and the Wallasey Tunnel approach road was blocked in both directions.
Merseyside Police said traffic was being diverted but motorists were advised to avoid the area and find alternative routes where possible.
Traffic information service Inrix said: “Wallasey Tunnel Approach in both directions blocked, queueing traffic due to police incident between M53 J1 / A5139 Dock Road / A554 (Wallasey) and A5139 Dock Road.
“Police have stopped traffic in both directions between the M53 J1 and the Wallasey (Kingsway) Tunnel.”
A police spokesperson said: "At this time Mill Lane and Poulton Road are closed, which is affecting traffic to and from the Wallasey tunnel, so motorists are urged to avoid the area where possible."
By 4pm, there was still queuing traffic and delays around the area but all lanes had been re-opened.
Merseyside Police said a 27-year-old male was detained by officers under the Mental Health Act and taken to Arrowe Park Hospital.