The shocking incident took place yesterday evening in the Gosport area, Hampshire police has said.
The distressed female, who is in her 20s, was found on a cycle path between Long Drive and Rowner Lane at 7.50pm.
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Police say she described being ‘forced’ into an orange-coloured van by a man she did not know, in Station Road between 3pm and 4pm earlier that day.
The woman was then driven to an area of woodland where she was physically assaulted, before she ran from her attacker, police said.
Detective Inspector Dal Andrews said: ‘This was a very distressing incident for the woman involved. We have a number of officers out making enquiries in the local area, reviewing CCTV and doorbell footage and conducting house to house enquiries to build up a broader picture of the circumstances of this assault.
‘At this very early stage of the investigation, we are providing support to the victim and working with her to identify the exact time frame of this incident, the locations where the offending took place and further details about the man responsible.
‘When we have further details to share with you we will do so, but in the meantime we would like to hear from anyone in Station Road and the surrounding areas who has a CCTV camera or doorbell camera as we would like to review the footage.
‘In addition, we ask the public to please report any suspicious behaviour – whether this be suspicious people or vehicles – in the Gosport area to police.’
Police patrols have since been stepped up in the area.
Chief Inspector Fifi Gulam-Husen, district commander for Fareham and Gosport, said: ‘This incident will undoubtedly be of particular concern to the local community.
‘I want to reassure the public that this is being investigated thoroughly, and in addition to the detectives making enquiries into this offence, we also have support from neighbourhoods officers and response and patrol officers who will be carrying out regular patrols across the borough.
‘Stopping violence of this kind is an absolute priority for us as a Force and we are working hard alongside our partners to make the borough a safer place for all.’
Chief Insp Gulam-Husen urged people to use the Street Safe online tool to report trouble spots in the community. It can be found at: police.uk/pu/notices/streetsafe/street-safe
Anyone with information about Tuesday’s attack, or the person responsible, is asked to contact police immediately on 101, quoting 44220153483.
Alternatively, contact independent charity Crimestoppers, anonymously, on 0800 555 111, or via their anonymous online form at crimestoppers-uk.org