Hundreds of Glasgow shops and pubs are selling counterfeit cigarettes from under the counter and behind the bar.

The Evening Times bought a huge haul of fake fags during a sting operation with five former undercover police officers.

The team is tasked with gathering intelligence on the multi-million pounds trade in illicit tobacco - which one former Scotland Yard detective warned is funding terror groups in Northern Ireland.

Shopkeepers who sell counterfeit tobacco risk a seven-year prison sentence but many in Glasgow are “brazenly” selling the products which have been found to contain rat poison, asbestos, arsenic, dead flies and even human faeces.

Read more: Hundreds of pounds worth of fake fags for sale in Glasgow shops and pubs

One newsagent in the south side of the city opened a drawer stuffed with hundreds of packets of fake fags in full view of customers.

Others kept their haul out of sight, either in locked cabinets behind the counter or in storage space at the back of shops.

Counterfeit cigarettes and illicit tobacco is also available from behind the bar at dozens of pubs, and from punters selling from supermarket carrier bags.

A packet of twenty can cost as little as £2.50, while a 50g pouch of tobacco can change hands for under £10.

Counterfeit products often come in packaging which is identical to leading brands but experts can identify whether they are fakes by checking serial numbers.

The former police officers are also on the lookout for contraband which is not licenced for the UK market, and illicit whites – cigarettes which are smuggled in from overseas and often have different languages on the labels.

Former Scotland Yard Detective Chief Inspector Will O’Reilly, who has led hundreds of test purchasing operations in the UK, Ireland, Eastern Europe, Australia and New Zealand, said: “Glasgow is up there with some of the worst we’ve been to. We find illicit tobacco products very easy to buy in Glasgow.

“It is mainly food shops and convenience stores. It’s quite blatant. Most of the shops are selling illicit tobacco products. You can also get these products in thrift shops and pubs.

“What is interesting in Glasgow is the amount of illicit whites, which are manufactured purely for smuggling. They’re not brought over by people smuggling a carton or two in their luggage. They are brought in in bulk, normally in shipping containers by organised crime gangs, using their distribution routes used historically for drugs to distribute them around Glasgow and Scotland.

“They can make at least £1m in profit from every container they successfully get in. They can be bought as cheap as £2.50 a pack. Depending on the brand, it can be up to £3.50. You then get counterfeit products which are £4 or £5 and then £5.50 to £6 for the contraband products.

“I know a lot of people think they aren’t hurting anybody – they think it’s a just a cheap smoke – but there is more to it than this. Every pack they buy – especially the illicit whites and counterfeit products - are funding organised crime.

“We also see a strong link between the trade in Scotland and terrorist organisations in Northern Ireland, from both sides of the political divide.”

Chief Inspector Ronald Megaughin, Deputy Director of the Scottish Business Resilience Centre, also issued a stark warning about illicit tobacco.

He said: “The trade has devastating consequences throughout the supply chain - from the manufacture of the goods in unregulated factories with appalling conditions, through to the resulting profits from the end sale - which can often fund serious organised crime and even terrorism.

“For items such as tobacco the end user can also become the victim. The inferior tobacco and cigarettes can contain all manner of dangerous ingredients, with tests showing them to contain harmful metals designed to 'bulk out' the product.

“It is important that consumers change behaviour, and appreciate that there consumer habits have consequences. They are in no way getting a bargain.”

Targeted test purchasing by Mr O’Reilly’s team in Glasgow’s east end last month uncovered a thriving trade, with Mr O’Reilly’s team able to buy products from more than thirty sources.

A similar operation in the south side of the city this week saw former police officers buy illicit tobacco from dozens of shops and pubs.

The intelligence gathered in Glasgow will now be passed to local trading standards officers and Her Majesty's Revenue and Customs (HMRC).

Mr O’Reilly, who carries out research on behalf of tobacco firm Philip Morris International, added: “They do follow up on the intelligence we give to them which has in the past led to really big seizures. So, hopefully they will follow this up, search some of these places and bring people in front of the courts.”

A spokesman for HMRC said: “The market share for illicit cigarettes was estimated to be 10% in 2014/15, and 35% for hand-rolling tobacco. Collectively, these illicit markets cost taxpayers an estimated £2.1bn.

“Since 2000, HM Revenue and Customs has more than halved the size of the illicit market in cigarettes; in the last two years alone, over 3.1 billion illicit cigarettes and over 642 tonnes of hand-rolling tobacco have been seized, resulting in 745 prosecutions.”