The incident took place on Saturday, April 17, in Kidderminster.
Officers received reports between 8.15pm and 8.30pm that a man and woman were both assaulted with a glass bottle by a group of men between Blackwell Street and High Street.
Both victims suffered serious injuries to their heads and required urgent medical attention.
CCTV footage shows a number of people and cars passing through the town at the time.
West Mercia Police is asking anyone who witnessed the assault, or who has dash-cam footage to get in touch and quote log number 677i of April, 17 2021.