Kent Police is appealing for information after three people reported being assaulted in Sheerness.
The incident happened in Beach Street between 6.55pm and 7.05pm on Sunday 20 August 2023.
It is alleged a man and two women were approached by a group of people they did not know and, following a verbal altercation, they were assaulted.
The woman later attended hospital for treatment to a serious head injury and has since been discharged.
Investigators have completed house-to-house enquiries and a review of CCTV footage and are now appealing for witnesses or anyone with information to contact them.
Residents with private CCTV and motorists with dashcam are also asked to check for relevant footage.
Anyone with information should call 01795 419119, quoting reference 46/150341/23.
You can also call Crimestoppers anonymously on 0800 555111 or complete the online form on their website.