A woman has been raped after she went to check on an abandoned car seat.
The attack took place around midnight on Monday, August 16 in a layby on the A4 in Thatcham.
The woman reported she stopped her car on the A4 after noticing the car seat in the layby and she feared a child could be in danger.
Thames Valley Police said they are appealing for witnesses.
Police have been investigating whether the empty car seat is linked to the crime.
Investigating officer Detective Inspector Alice Broad said: "The investigation is working at pace to identify the suspect of this offence.
"The victim has provided a full account of the incident and is being supported by specially trained officers. Due to the victim’s account, we are now in a position to provide further information to the public.”
Detective Broad confirmed they believe the offender was not known to the victim.
"Thames Valley Police is working to understand the significance of the child’s car seat and whether it is linked to the offence,” she added.
“However, to ensure the safety of the public, we would advise that if you see anything in a road or on the roadside that concerns you, make a note of the precise location and call Thames Valley Police on 101. The force can make appropriate checks."
The force has urged anyone with footage from the A4 in Thatcham between 11pm on Sunday, August 15 and 12.15am on Monday, August 16 to come forward.
Detective Broad added: "This is a concerning incident that has understandably caused anxiety in the local community. However, such offences are extremely rare and a thorough investigation is underway to identify the offender.
"You will see more officers out and about in the area and I urge you to speak with them if you have any questions or concerns that you wish to raise."
Anyone with any information should call 101 quoting the reference Op Fax 43210366130. You can also call Crimestoppers on 0800 555 111.