Although prisons are normally associated with being locked in, hundreds of public sector employees faced being locked out of their penitentiary workplaces should an ongoing labour dispute not be resolved.
With a deal on new terms for public sector workers in Denmark yet to be reached, industrial action in the form of a strike or retaliatory 'lockout' looks likely to hit public services in the country.
The contract (overenskomst in Danish) affects people employed by the Danish state, regional authorities and in municipalities.
Negotiations between those authorities and trade unions have hit several obstacles, leaving strike or 'lockout' - a temporary denial of employment by the public sector authorities as a response to the dispute - as a possible outcome.
The Prison Service has confirmed that up to 1,000 of its staff could be affected by the lockout.
That figure includes employees carrying out social work or teaching, legal administrators and I.T. workers.
But the majority of the service's employees - its 3,000 male and female prison officers - would not be encompassed by the potential strike or lockout.
Staff required to ensure that the "most critical tasks can still be completed" would be exempted from any industrial action, the Prison Service confirmed.
As such, prison officers will still be on hand to lock inmates in, regardless of whether colleagues face being locked out.
Health and kitchen personnel, as well as essential academic and administrative staff, will also be able to continue working during any potential freeze caused by the labour dispute, the Prison Service said.