Police are trying to trace a cyclist following a fatal crash in St Albans on January 9 in which another cyclist died.
Hertfordshire Constabulary is investigating the death of cyclist Mark Greenwood, who died after an accident with a silver VW Golf, in Redbourn Road, at around 6.25pm.
Investigating police constable, Dave Clarke, said: "Following an initial appeal about the collision, a number of people have contacted us and we are now aware that another cyclist passed Mark prior to the collision.
"This cyclist stopped on Punchbowl Lane to deal with a puncture before going on his way. I would like to appeal to this man, who would not have known the collision occurred, to contact me."
Anyone with information can contact PC Clarke at Hitchin police station on 101 quoting ISR 463 of January 9.
A 24-year-old man from St Albans has been arrested on suspicion of causing death by dangerous driving and released on police bail until April 7.