A manhole cover was at the centre of a road accident in Chorley in which an elderly cyclist was killed, the Local Democracy Reporting Service (LDRS) understands.

An appeal issued by Lancashire Police for witnesses to the incident – which happened on Cowling Brow on August 14 – described how the man, in his 70s, “struck a hole in the road” and was thrown from the electric bike he was riding.

However, it is believed the defect was not a pothole in the road surface, but rather the metal cover of a fire hydrant which had sunk beneath its surrounding rim.

Tar has now been laid across the danger spot as a temporary safety measure until it can be properly rectified.

In pictures taken on behalf of the LDRS, the sunken cover can just be seen at the edge of the short-term repair. The surrounding road surface has also started to crack, but has not itself dipped significantly.

The police appeal was made on Saturday, almost a month after the unnamed pensioner had come off his bike. He spent more than two weeks in hospital with serious injuries before dying on August 31.

As the highways authority, Lancashire County Council has an overarching responsibility for carriageway safety and carries out routine inspections of the roads within its network – on a monthly, quarterly and six-monthly basis, according to the strategic importance of the route.

However, the situation is most clear cut when it comes to traditional potholes – with County Hall having a series of targets for speed of repair following their reporting or discovery, depending on the urgency of the problem and the classification of road on which the defect has occurred.

A spokesperson for Lancashire County Council said: “We are very sorry to hear about this incident and our thoughts are with the family and friends of the gentleman who has died.

“We are looking into the circumstances of what happened and will fully co-operate with the police investigation.”

The LDRS has also approached United Utilities for comment in relation to the fire hydrant cover.

Anyone who witnessed or has dashcam, doorbell or CCTV footage of the accident, which happened at around 10.30am on August 14, should call police on 101, quoting log 1330 of September 6.

Alternatively, the Serious Collision Investigation Unit can be emailed at SCIU@lancashire.police.uk.