Police are appealing for night-time revellers to come forward if they witnessed incidents which involved knives in Gloucester city centre over the weekend.
There were two incidents in Eastgate Street which are being treated as linked and are understood to involve groups of young males who are known to each other.
Shortly before midnight on Friday police were called after a teenage boy on a bicycle smashed a car window with a weapon while there were teenagers inside.
The front passenger, a teenage boy, received a cut to his hand from the shattered glass.
Officers attended and the cyclist had fled the scene. Following further information four other males aged between 16 and 20 were arrested on suspicion of affray. One of them was also arrested on suspicion of possession of drugs.
No weapons were found during searches and they have since been released on police bail with conditions which include a curfew.
The following evening at around 11.30pm police were again called to Eastgate Street, with a report that a different man had threatened another male with a weapon.
Officers attended and the offender had fled. No injuries were reported and at this stage no arrests have been made in connection with the incident from Saturday night.
Enquiries are continuing and police are now appealing for anyone who was in the area around that time to come forward if they have not already spoken to police. Officers are also keen to hear from anyone who may have dashcam or mobile phone footage of those involved.
Inspector Si Motala, of Gloucester Neighbourhood Policing Team, said: “We will not tolerate this dangerous behaviour and we are doing everything in our power to bring these individuals to justice.
“While these incidents will be frightening for people to hear about, these young males who are involved are known to each other, and I would urge their parents and carers to take responsibility for your children, be aware of where they are, what they are doing and who they are with.
“Over the coming days and evenings, we are increasing patrols in the area, and we ask for anyone who sees a crime taking place and if the offenders are present or nearby to call us immediately on 999.”
Information can be provided to police online by completing the following form and quoting incident 583 of 23 September: www.gloucestershire.police.uk/tua/tell-us-about/cor/tell-us-about-existing-case-report/
You can provide information anonymously to independent crime-fighting charity Crimestoppers online here https://crimestoppers-uk.org/give-information/forms/give-information-anonymously or by calling 0800 555 111.