Three teenagers were arrested on suspicion of robbery within an hour of police being contacted following an incident in Billericay High Street.
At about 5pm on Sunday January 7, police received reports of three suspects wearing face coverings approaching a member of the public and demanding their phone.
When the victim refused, one suspect reportedly revealed a knife, and the victim gave them their phone.
Within 30 minutes, officers traced the movements of the suspects to Basildon Station and onto Rayleigh Station.
Two suspects were arrested in Rayleigh at about 5.45pm, and a third was arrested seven minutes later after they attempted to evade officers on foot.
The three have been bailed until March 10 2024.
If you have any information about this incident that may assist police, please get in touch quoting incident number 42/3606/24.
You can submit a report on the website www.essex.police.uk/digital101 or use the online Live Chat service available Monday to Friday (excluding public holidays) between 10am-9pm.
Alternatively you can call 101.
If you would like to make an anonymous report you can contact independent charity Crimestoppers, by visiting their website or by calling 0800 555 111.