Police Scotland is paying £600,000 in rent for a former HQ building they no longer use.

The national force has inherited the long-term lease over the one-time base of the elite Scottish Crime and Drug Enforcement Agency

But it has failed to sub-let the building, Osprey House near Glasgow Airport, since staff moved out after the single force was created in 2013, mostly to the world renowned Scottish Crime Campus at Gartcosh.

Now the force is stuck in a lease, signed in 2012, just a year before the SCDEA was abolished, that runs through to 2022.

Tory MSP Douglas Ross told the Sunday Post: "It's quite incredible that Police Scotland will pay a seven-figure sum for a building it never uses.

"The whole point of a single force was to improve efficiency. Instead, we have a situation where taxpayers' money is being spent for no gain whatsoever."

Senior police figures have long warned that they have inherited an estate - the police stations and offices blocks - that is not a good match to its operations. This includes run-down buildings, such as the former HQ of Dumbarton division of the old Strathclyde Police or the former HQ of Northern Constabulary, which are expensive to maintain and far bigger than needed.

The Scottish Police Federation has als complained that its members have to work in substandard accommodation. Several former HQs, such as Strathclyde's Pitt Street, have been put on the market.

Alan Cormack, Police Scotland's estate manager, said: "We are actively looking for options for the future use of Osprey House either within Police Scotland or new people taking on the use of the building.

"The offices are vacant and have been since April 2015. In the meantime, we are responsible for the upkeep and maintenance of the building. The costs for this, including rent and rates, were £598,472, in 2015-16."

The lease for Osprey House was signed by the old Strathclyde Police, which acted as landlords to the SCDEA, which was responsible for Scotland-wide operations against organised crime. The SCDEA function of Police Scotland is now based at the much larger £75m Gartcosh facility, which belongs to the Scottish Government.