Ipswich - Seven men sentenced for cannabis production and cocaine supply

A group of seven men, five of who are from Ipswich, have been sentenced for their part in the large‑scale production of cannabis and supply of cocaine across Suffolk.

Four of the individuals received jail sentences totalling over 28 years.

The defendants — Dean Yule aged 52 of Kemball Street in Ipswich, Michael Harty aged 55 of Chelmsford, Robin Southgate, aged 55 of Portland Way in Ipswich, John Leighton aged 36 of New Cut East in Ipswich, Haydon Grey aged 35 of Cardiff Avenue in Ipswich, Warren Sherman  aged 25 of Sheldrake Drive in Ipswich and Tuan Nguyen, aged 29 from Blue Bell Hill Road, Nottingham.

The sentencing took place yesterday (Tues 17 February) at Ipswich Crown Court.

All seven men pleaded guilty to conspiracy to produce cannabis between September 2024 and July 2025 at an earlier hearing.

Harty also pleaded guilty to the additional charge of being involved in the supply of cocaine, possession of criminal property and production of class B drugs.

Yule pleaded guilty to being concerned in the supply of class A drugs and possession of criminal property. Southgate also pleaded guilty to possession of criminal property. Grey also admitted dangerous driving.

Harty received a 12 year jail sentence, Yule was sentenced to 10 years in jail, Southgate received four years, two months in jail and Nguyen received a sentence of 30 months.

Leighton received a 10 month jail sentence, suspended for 18 months, Grey was sentenced to a 15 month jail sentence, suspended for 18 months and Sherman received a community order for 18 months and ordered to do 150 hours unpaid work.

(Above left to right: Yule, Harty, Southgate, Nguyen)

The group operated a sophisticated network centred around industrial units and rural locations in Suffolk. Police also seized cocaine with a street value of £1.5 million.

Police identified three cannabis factories attributed to the conspiracy using surveillance and covert tactics. One at Lavender Hill in Ipswich, where officers discovered approximately 230 plants on 1 April 2025. Police investigations established that repeated visits to the location by Yule and Harty took place.

A second factory was located at Waterloo Road in Ipswich where 705 cannabis plants were located in May 2025.

On entering the premises officers immediately encountered a temporary living area where defendant Hoang Hai was located. The police investigation established he had been transported to Ipswich by individuals connected to the conspiracy and coerced into tending to the plants.

Hai, aged 38, was arrested for production of cannabis and in October 2025  was sentenced to 44 weeks in prison.

A third factory was located in Crowfield, where 120 young cannabis plants were seized in May 2025. It was here that Grey and Sherman were arrested after being observed clearing the site with Southgate.

Enquiries also established that Yule, Southgate, and Grey attempted to secure a fourth site at Denham near Eye and were planning to grow cannabis on the land.

(Above - cannabis found at Lavender Hill)

Police enquiries led officers on 11 April 20205 to arrest Harty in Essex and a search of his bedroom within the property in Brentwood resulted in the seizure of a significant amount of cocaine worth in the region of £1.5 million pounds.

A container at Crowfield was identified as a suspected cocaine store used by Yule. He made repeated short visits in suspected drug dealing transactions with other individuals. On 1 July 2025, officers seized a significant quantity of cocaine from the container after arresting Yule, Southgate, and Leighton.  

(Above - Cannabis find at Waterloo Road)

Nguyen was arrested in Nottingham in September 2025 and subsequently charged.

Harty, Southgate, Yule, Leighton and Grey were all charged on 2 July 2025, whilst Sherman & Grey were charged in August 2025.

During coordinated police warrants on 1 July 2025, substantial quantities of cannabis, cocaine, cultivation equipment, mobile phones, and luxury goods were seized from addresses linked to the defendants, including Yule’s home, Southgate’s residence, Leighton’s boat on Ipswich Marina, and units at both Broomvale Farm and Woodfarm Business Centre.

(Above: Cocaine found at Harty's property)

In a police interview Leighton admitted towing trailers and helping at Waterloo Road but denied knowledge of the cannabis operation, claiming he acted under duress due to a cocaine debt.

DC Chris Townrow of the Serious and Organised Crime Unit said: “The sentencing of these seven individuals sends out a clear message that we will robustly deal with individuals that are involved in organised criminality and those that blight our communities by dealing drugs.

“The fact they all pleaded guilty at an early stage demonstrates the compelling evidence that was compiled and that they were facing.

“This group operated sophisticated, commercial‑level cannabis factories and exploited vulnerable individuals. Their actions brought harm to our communities and generated illegal profit.

“The impact drug supply has on communities is significant and our work to disrupt this criminality continues apace, using all the legislation available to us."

If you suspect drug dealing is taking place in your area or see anything suspicious or out of place, please tell us. You don’t have to be certain, just concerned. Call police on 101, or alternatively you can contact the independent charity Crimestoppers to report anonymously – either online at www.crimestoppers-uk.org or by calling 0800 555 111.

Det Sgt Nick Shirley, also of the Serious and Organised Crime Unit said, “This investigation is the result of tireless team work to lock up a group of career criminals.

“The fact they all pleaded guilty at an early stage demonstrates the compelling and comprehensive case that was built by the OIC and the wider team, and demonstrates that Suffolk Constabulary will not tolerate  the threat posed by serious and organised criminals operating in Suffolk and beyond.”