A cyclist in his 70s is thought to have suffered "life-changing injuries" in a crash involving an agricultural vehicle.
According to police in Hertfordshire, the cyclist and driver were involved in the crash - described by officers as "serious" - at around 10.30am on Sunday, August 28.
The incident took place on Baldock Road, Wood End, near Ardeley.
Police officers and East of England Ambulance Service paramedics attended. The cyclist - a man in his 70s - was taken to hospital.
PC James Wingate, from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: "I’d like to hear from anyone who witnessed this collision, who has not already spoken to us.
"It is believed other cyclists were in the area and may have seen what happened or captured footage on head-cams which could assist our enquiries into the circumstances of the collision."
Witnesses can contact Hertfordshire Constabulary with information online (https://www.herts.police.uk/) or by phone on 101, quoting ISR 238 or August 28.
Alternatively, reports can be handed to investigators 100 per cent anonymously through CrimeStoppers online (https://crimestoppers-uk.org/) or by phone on 0800 555 111.
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