Police are currently searching the River Mersey underneath the Runcorn Bridge, close to the scene of a murder arrest.
An underwater search unit has been station at the scene of the Silver Jubilee Bridge after a man was arrested on suspicion of murder yesterday.
Officers arrested the 43-year-old man after they were called to concerns about the behaviour of a man spotted there on the night of Saturday, February 12.
READ MORE: Second man arrested as part of Runcorn Bridge murder investigation
Cheshire Police contacted Merseyside Police after a member of the public reported seeing a man parking his car and acting suspiciously between 8.30pm and 9pm on the bridge.
Merseyside officers then visited a number of houses in St Helens, where the 43-year-old was arrested on suspicion of murder and taken into custody.
A joint Merseyside Police and Cheshire Police investigation into the circumstances continues and house-to-house and CCTV enquiries are being carried out.
This morning divers are also believed to be searching the River Mersey under the bridge, as an underwater search unit has been spotted on Collier Street.
Detectives are appealing for witnesses and dashcam footage following a report of suspicious activity on the Runcorn Bridge on Saturday evening.
Detective Superintendent Steve Reardon said: "We have spoken to members of the public who have already come forward, and are grateful for their assistance.
"We are still very keen to speak to anyone else who may have driven across the Silver Jubilee/Runcorn Bridge between 8.30-9pm on Saturday, and saw a man acting suspiciously.
"You may have information that could prove vital to our enquiries as we try to piece together exactly what took place.
"We are particularly keen to hear from anyone who has dashcam and drove over the bridge at that time - please check for anything that might be significant and send it to us."
Anyone with information on this incident is asked to contact Merseyside Police social media desk via Twitter @MerPolCC or Facebook Merseyside Police CC with reference 22000106196.
Merseyside Police are requesting for anyone using the Bridge at this time with dashcam footage to upload it using this link.
You can also call 101 or contact the independent charity Crimestoppers anonymously, on 0800 555 111 or via their online form at: https://crimestoppers-uk.org/give-information/give-information
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