Spanish police have busted a gang that ran three illegal tobacco factories – where Ukrainian refugees worked in poor conditions.

Operations in three regions of Spain lead to 27 arrests being made amid allegations the gang smuggled large quantities of tobacco, turned into counterfeit cigarettes.

The factories could make more than half a million cigarette packs daily, sold across Spain and abroad.

Ukrainians, who had fled Russia’s invasion of their country, were living crammed into prefabricated shelters within factories.

They were working long hours and were not leaving, to avoid detection, as some had entered the country illegally.

Bosses of the organisation enjoyed a life of luxury, allegedly laundering money for their tobacco smuggling operation.

Authorities seized tobacco products worth €37.5m ($41m; £33m), luxury vehicles, jewellery and large quantities of cash during their raid after homes, industrial buildings and shops were searched.

The first clandestine factory was found in a chicken shed near Seville in the south at the end of 2021 that lead the authorities to uncover two other operations, in the eastern Valencia region and La Rioja in the north.

Police said the gang was also diversifying production, by developing large marijuana plantations.

Investigations got assistance from the European policing agency Europol.

The United Nations said there was almost eight million recorded Ukrainian refugees across Europe, who fled Russia’s February 2022 invasion – with 160,000 registered in Spain.

The European Parliament reported labour exploitation of Ukrainians was on the rise, saying the urgency of their situation and language barriers sometimes forced refugees to take informal and underpaid work.

Tobacco products worth €37.5m, luxury vehicles, jewellery and cash seized.