A four year old girl was taken to hospital with serious injuries after she was hit by a van in Hook on Sunday.
Police were called at 11.45am after the collision on the A30 in Hook, close to St John's Church.
The girl's family are aware and are with her.
Officers investigating the collision would like to hear from anyone who was in the area at the time and saw what happened.
A police spokesman said: "We are particularly keen to hear from anyone with dash cam footage capturing the collision or the moments leading up to it."
No arrests have been made.
The A30 was closed in both directions while emergency services attended.
Anyone with information is asked to call 101 quoting incident number #0851 of September 3.
Alternatively, go online and submit information via https://www.hampshire.police.uk/tua/tell-us-about/cor/tell-us-about-existing-case-report/