Mountain of cardboard, drink caps and other items found near Gdansk port city.
Seventy tons of waste meant for recycling is already on its way back to the UK.
Environment Agency is investigating how the recycling ended up there.
More than 220 tons of recycled waste from Britain has been found dumped in a warehouse in Poland, and will now be returned at the taxpayers’ expense.
The mountain of cardboard, drinks packets, aluminium foil, paper and other items painstakingly sorted by Britons to help save the planet was discovered abandoned in Bogaczew, 72miles from the port city of Gdansk.
Seventy tons of the waste is already on the way back to the UK – as the Environment Agency confirmed it was launching an investigation to find out how the waste got there.
It comes as Malaysia announced it would return 42 containers containing British plastic waste last month, stating it did not want to become ‘the garbage dump of the world’.
A spokesman for police in Elbag, near Bogaczew, said: ‘The investigation to determine the exact origin and purpose is still ongoing.
‘The case is an investigation and is conducted under the supervision of the District Prosecutor’s Office in Elbl*g, in cooperation with the customs and environmental services from Poland and Great Britain.
‘Part of the illegal waste from Great Britain is already on the way back.
‘The case dates back to spring 2018, when police from Elbl*g received information that illegally stored rubbish is likely in Bogaczew near Podlasie.
‘The department fighting economic crime took care of it. 150 tons of stored waste was found on site.
They were mixed and pressed commercial rubbish.’
The rubbish – which also includes Pedigree dog food, Kenco coffee packets and crisp packets – was found in spring 2018.
Further surveillance also led to the detention of a truck from the UK in Bogaczewo, also carrying waste from the UK.
The City Police of Elbag have said since the discovery of the waste, customs officers intercepted a further two containers with similar contents at the port of Gdynia.
Polish authorities claim early investigations suggest it is from the UK, and around 150 tonnes of waste is awaiting transportation back.
A local source said: ‘During the investigation, police found that the illegal rubbish came from England – officially as a rubbish from recycling.
‘The cost of the transport will be paid by the United Kingdom.’
An Environment Agency spokesperson said: ‘The illegal export of waste is a crime and we will not hesitate to take action against those responsible with offenders facing either a two-year jail term and an unlimited fine.
‘We are working with the Polish authorities to investigate the circumstances around these particular exports and will take appropriate action to hold those responsible for the exports to account, should there be any evidence of wrong-doing, and ensure any illegally exported waste is repatriated to the UK.’
Published on dailymail.co.uk