A man was left struggling to breathe after being sprayed with an unknown gas in Derbyshire.
The incident occurred on Sunday February 17 on Warner Street in Derby at around 7.30pm.
Police have now issued a CCTV image of two girls, believed to be around 16 years of age, who were seen in the area at the time.
Officers would like to speak to the girls in connection with the incident.
The man was left struggling to breathe for a short time after the incident.
Anyone with any information is asked to contact police, quoting the incident number 19*84060 and the name of the officer in the case PC Warner, by calling 101 or via the online contact form at www.derbyshire.police.uk/Contact-Us.
Alternatively, call Crimestoppers anonymously on 0800 555 111.