These fortresses protect both the housing estates of the future and the interests of the criminal masterminds who use them to launder dirty money from drug
dealing and other crimes.

Inside most of the sites is a lone security guard in an isolated cabin. Many know nothing of the organised criminal networks for which they provide a front, but some are breaking other laws.

As we squeeze through gaps in the metal fences at sites around Barrhead, teams of officers across Strathclyde are simultaneously raiding dozens of premises.

Specialists from the UK Border Agency and the regulator, Security Industry Authority (SIA), join us to check whether the guards are in the country legally and hold the appropriate licences. Staff from the Department for Work and Pensions also check for benefit fraud.

Under new SIA legislation, door supervisors, security guards, CCTV operators and bodyguards require a licence or face a £5000 fine or six months in prison. The employer could get unlimited fines and a jail sentence of up to five years.

Traipsing through the mud past silent cement mixers and JCBs, Detective Sergeant Joe McKerns, one of the
officers leading the campaign, explains their aims. “We want them to know they can no longer operate with impunity,” he says. “It is about disrupting their lifestyle as they have been disrupting everyone else’s.

“We now have a really good idea of who and where the groups are. These groups are only interested in crime and money. They don’t care about what commodity they’re dealing in -- whether it’s drugs, guns or human trafficking -- and they don’t care about the victim as long as they’re making money.

“We have got to give
legitimate companies the chance to work without threats or intimidation.”

DS McKerns says the most important thing is the message it sends to firms working illegally, and the breathing space and respite it offers to legitimate companies. At each site we visit, officers check identification and licences to ensure they are legitimate. Those caught working illegally are removed.

This is the biggest operation the force has run on the security industry since the campaign on organised crime began at the end of August, and is just one part of a broader strategy that aims to cut off money flow to those in organised crime.

Another major facet is preventing firms with direct links to organised crime from obtaining public contracts. Officers point out that their efforts to trace money from ill-gotten gains is far more difficult once it is mixed with funds from
quasi-legitimate businesses.

Serious organised crime can sound detached from most people’s everyday reality. It is easier to see the links between vandalism and antisocial behaviour and the everyday impact on people’s lives, because these crimes are so visible. Yet organised crime is a £2.6bn industry in Scotland and, while almost all the groups in Scotland are involved in Class A drugs, what the public may be less aware of is that they are also behind the companies transporting passengers and patients, developing properties, guarding schools.

“These people live in normal neighbourhoods and many people know who they are, often because they have the biggest house and drive a flashy car without having a job,” says DS McKerns.

“The public need to be aware of the impact this has on them. The intimidation and vandalism doesn’t just affect the builders, but the parents waiting for a new school to be built, or patients waiting for a hospital. We need people to come
forward with information.”

Groups trafficking drugs are also behind some of the companies vying for and often winning public contracts funded from taxpayers’ pockets. As the Strathclyde strategy states: “It is an inconvenient fact that the public services of Scotland may be unknowingly and unwittingly financing
organised crime.”

In the briefing room on Glasgow’s Helen Street, Inspector Davie Aitchison, the divisional violence reduction co-ordinator, explains: “Many of them use the major security firms in the west of Scotland as a front and we know they exploit people including foreign nationals.

“There is a lot of money at stake for these companies and a lot of these companies will be wanting in on the Commonwealth Games contracts. We want to ensure that only legitimate businesses have that opportunity.

“We know the problems the private security sites present us, with vandalism, fire-raising and assaults being carried out. I am not saying it is a war going on, but there are definitely tit-for-tat tactics between rival firms run by organised crime.” The force’s new strategy warns there may be a violent backlash as a result of their concentrating on such groups, but that this “growing concern” has to be tackled, particularly before major new projects such as the 2014 Commonwealth Games and the new Southern General Hospital.

Politicians have said that some £1bn will flow into major infrastructure projects as part of the run-up to 2014, and the hospital redevelopment is worth £842m.

The Commonwealth Games site, currently being cleared, has already been firebombed and the perpetrators are thought to be a rival security firm. At least one petrol bomb was thrown at machinery on the site of the village in Dalmarnock on September 7, the day a new firm began its contract. The following night, the digger was wrecked on the land, which will be home to 8000 athletes in 2014.

Four years ago, the then president of the Association of Scottish Police Superintendents, Tom Buchan, named several “rogue” private security firms he said had links to criminal gangs involved in drug dealing, extortion and money laundering. Since then the SIA has introduced an “approved” contractor scheme and several forces have introduced units to tackle vandalism and violence between security firms, but police believe the problem has escalated.

The Strathclyde strategy paper states: “Infiltration of the private security industry and taxi industry (primarily the private hire taxi industry) by organised crime groups in the force area is not a new problem, but is a significant and growing concern.

“The problem is well rooted and, increasingly, these groups are branching out from their traditional territories to other regions in Scotland. Other police forces have identified several private security companies operating in their area which have their primary base and control among organised crime groups in Strathclyde.

“Groups who operate criminal security and taxi companies operate in a number of ways, often rebranding companies, changing staff and employing different intimidation tactics in an attempt to mask their criminal activities. Despite this, intelligence reveals specific operating behaviours and tactics for these companies.

“The need for a comprehensive multi-agency strategy is made all the more timely by the following factors: major construction work for the 2014 Commonwealth Games; significant ongoing and proposed building projects, eg M74 and M80 extensions; major Scottish Government, public and local authority building projects, eg the Southern General Hospital in Glasgow.

“Many of the contracts obtained by security and taxi companies which are fronts for organised crime are ‘public’ contracts or are achieved through sub-contracting services to major construction companies working on public contracts.”

The strategy also warns that criminal companies are increasingly diversifying into providing security and door stewards for pubs and clubs. Last month, Kenny MacAskill, the Justice Secretary, called on the public to work with police to clamp down on organised crime, just days after The Herald reported Strathclyde Police’s decision to write to NHS Greater Glasgow Health Board to recommend it does not go ahead with a £2m taxi contract to a firm previously linked to organised crime.

Senior officers say it is a problem that can only be tackled alongside other partner agencies and with the support of the public. Phil Taylor, regional director of the UK Border Agency in Scotland and Northern Ireland, said: “This successful operation shows our commitment to work with our colleagues in police forces throughout Scotland to uncover crime caused by illegal immigration.”

John White, the JobCentre Plus area fraud investigator, said: “This [operation] is an excellent example of how we work with other agencies to root out benefit fraud. We are committed to deterring those considering fraud.”