A video being shared on social media shows several officers holding a man down in front of cars on the Rohais.
On Tuesday (16 September), Guernsey Police were searching for a man involved in a 'serious investigation'.
The force says, when officers approached a 32-year-old as part of their enquiries, he fled, leading to a pursuit.
The man was detained and arrested on suspicion of possession of controlled drugs with intent to supply, and resisting arrest.
The arrest was recorded by a driver stuck in a queue of cars in the Rohais, and the footage was shared widely online.
A relative claimed the man was injured during the arrest, namely suffering a broken nose.
Deputy Rob Curgenven, who's long had an interest in Guernsey Law Enforcement, told Island FM he has been contacted by the family of the man and is looking into it.
Guernsey Police have since issued a statement in response to questions about what happened.
"Officers called an ambulance to check the suspect for injuries, and he was cleared to be taken into custody.
"In custody, officers instigated another health check from a custody healthcare professional. He was referred to hospital, checked at the Emergency Department, and returned shortly after.
"The man was then bailed to allow for further enquiries."
Guernsey Police have confirmed that a complaint about the officers' conduct has been received by the Professional Standards Department.
The force says the video 'only shows a short part of the incident' and has asked that investigations be allowed to continue without further speculation.
It says information that could assist the investigation into the complaint or the criminal enquiry should be shared with Guernsey Police.
European praying mantis spotted in Guernsey garden
Guernsey's leisure centre reopens after near week-long closure
Beau Sejour remaining shut over weekend
Flyers advertising polar opposites delivered in Guernsey
Alex Scott named in England squad
Dangerous cycling on Guernsey roads
Closure ongoing at Guernsey's leisure centre
Guernsey's leisure centre closed for another day
