Justice 4 Leon has called for a public enquiry into the practises at Luton Police Station after the death of Istiak Yusuf on Saturday.
Mr Yusuf, 25, of Purley Centre, collapsed at the Buxton Road station following an arrest on allegations of domestic violence.
Police say that the 25-year-old “became ill” and died in his cell.
The incident comes 18 months after the death of Leon Briggs, who was held at the station under the Mental Health Act.
Following the incident five officers were suspended and the Independent Police Complaints Commission launched a probe, which has not yet concluded.
A campaign set up in the aftermath of Mr Briggs’ death has now called for increased scrutiny of Luton Police Station following Mr Yusuf’s death.
Justice for Leon’s Liberty Louise said: “We demand an inquiry into the procedures and protocol followed by Bedfordshire Police at Luton Police Station.
“This is the second death in two years, where a civilian has lost their life inside the cells at Luton.
“We demand action be taken now to look into the practices of Bedfordshire police at Luton Station, as there is evidently something very wrong occurring at the station which requires immediate attention.”
Liberty added: “We have another death in custody, that may or may not have been a result of police action, but regardless of this it is evident poor decisions have been made.
“These decisions have meant another loss of life for our community, another bereaved family that will have to suffer the onslaught of an IPCC investigation that seeks to blame the victim and not the perpetrators.
“We put it to the police and the IPCC that in these instances of deaths in custody, without police action, or indeed non action, these individuals would still be alive.
“Our joint campaigns will now be striving for a public inquiry into Luton police Station,and that it is done so,with the benefit of the community rather than the police in mind.”