Police have confirmed a biker died in a crash on which blocked the A5 in Northamptonshire on Friday (March 25).
A 46-year-old man from Dunstable was arrested on suspicion of causing death by dangerous driving and later released under investigation, pending further enquiries.
Crash investigators are appealing for witnesses to the smash, which happened at around at around 3.15pm.
Northamptonshire Police confirmed the rider was pronounced dead at the scene.
A spokesman added: "Crash investigators would like to hear from anyone who may have witnessed the incident or who may have dashcam footage of the collision or either vehicle prior to the incident.
"Anyone with information is asked to email [email protected] or call the Drivewatch Hotline on 0800 174615 or Northamptonshire Police on 101 quoting incident number 22000171416."
The A5 was closed between Towcester and Weedon for around six hours.
It is the fourth known death on county roads in just a week.
A woman later named as Daisy Jean Huddle, aged 20, died at the scene after a head-on crash involving her black BMW 1 Series and a white truck on the A45 between Stanwick and Raunds in the early hours of March 18.
Two people died — a 24-year-old woman and a man aged 40 — and another was critically injured in a three-car crash on the A6003 at Corby the following day.