A warehouseman who secretly helped run a synthetic drugs empire was jailed for three-and-a-half years.

Andrew Jones was arrested after UK Border Force guards seized five parcels containing £60,000 worth of synthetic "khat"-style drugs sent from China.

The parcels were all addressed to fictitious individuals at the company where Jones worked, Stirling-based V Tech SMT Ltd.

The company stocks equipment and supplies for the electronics industry, such as solder, but the parcels intercepted at Edinburgh, Heathrow and Coventry airports between January and July 2014 contained kilos of methylethcathinone, pentedrone hydrochloride and clephedrone.

One package alone, intercepted at Heathrow, contained £20,000 worth of methylethcathinone, also known as MEC.

The "designer drugs" or "dance highs" were legal in China until last year.

On Wednesday, Stirling Sheriff Court was told that Jones, 33, had agreed to act as the recipient for the high value parcels, but never made a penny out of the scheme because they never reached him.

Sheriff Wyllie Robertson told him, however, that anyone who was involved in bringing drugs into the country or who was involved in dealing could expect to be severely dealt with.

He said: "Having regard to the nature and gravity of these offences and the value of the drugs involved, no sentence other than custody is appropriate."

Sarah Lumsden, prosecuting, told the court that a police investigation had been launched after the parcels intercepted.

It was established that the names of the addressees on the parcels were false, and were not people employed by V-Tech, but that Jones had worked there for 10 years "in a warehouse role".

His home was raided, his desk at work and his works car were searched, and paperwork about the packages was found.

On a silver iPhone found on his desk and handed to police by his manager, officers found texted shipment notes and other messages made out to the fictitious individuals whose names were on the intercepted packages.

Miss Lumsden, the depute fiscal, said Jones was arrested and appeared in court on petition.

She said his case was originally intended for High Court trial, but was eventually reduced to sheriff court level.

Jones, of Newmills, Tullibody, pleaded guilty to being concerned in the supply of the substances, all Class B controlled drugs, at V-Tech SMT, where bosses had been totally unaware of what he had been up to.

Virgil Crawford, defending, said Jones had initially thought the substances were "what were commonly known as legal highs", but after the first shipment he was aware they were in fact prohibited drugs.

He said: "His involvement was to be the recipient of these packages sent into the country, but all were intercepted and there was no financial benefit to Mr Jones. He is not someone who has led a lavish lifestyle."