A 46-year-old man has been arrested on suspicion of dangerous driving and driving under the influence of drugs.
In a statement Leicestershire police said, "Shortly after 9.50am today (Wednesday 3 February), we received a report of a collision involving a cyclist and a van in High Street, Desford.
"The cyclist, a woman, has been taken to hospital to be treated for life-threatening injuries.
"A 46-year-old man has been arrested on suspicion of dangerous driving and driving while unfit through drugs."
High Street was closed off for much off the day while police continued their enquires. It's since been reopened.
UPDATE 14:57 03/02/21 - Recovery are now on scene and the road is being reopened. There will be no further updates.
— Leicestershire Police (@leicspolice) February 3, 2021