Police in the German state of North Rhine-Westphalia spent a total of €4.66 million on a new “innovation lab” which was originally set to cost just €250,000.

Among the itemised costs are a €35,000 kitchen, a €14,600 coffee machine and two chairs costing €6,000 each, Der Spiegel reports.

North Rhine-Westphalia’s audit office has criticised the spending and the lack of documentation to justify the growing budget.

“There was no economic analysis with statements on the needs and adequacy of costs,” the head of the audit office, Brigitte Mandt, said.

Police deny overspending and said the furniture and appliance choices were necessary to “integrate seamlessly into the existing infrastructure”.

Much of the budget was also spent on a robot dog which the force insists will be able to explore crime scenes and dangerous sites.