An investigation is underway after a south London council discovered that three cemeteries were being used to illegally dump building waste.
Southwark Council said what appears to be large amounts of builders' demolition rubbish has been deposited.
The three cemeteries are Camberwell Old, Camberwell New (known as Honor Oak) and Nunhead.
Council officials say some of the cemeteries now have contaminated soil, but no graves have been affected.
Annie Shepperd, chief executive of Southwark council, said the fly-tipping first came to light in December 2007.
"As soon as the council was aware of the scale and nature of the activity taking place we notified the appropriate regulatory body, the Environment Agency, which is now carrying out a criminal investigation into the events leading to the building material being deposited without permission."
Ms Shepperd said the areas used for burials are unaffected, but other, vacant land on the sites are now the subject of an industrial clean-up operation after contaminated soil was detected.
"No graves will be disturbed by this but when material is being removed areas of the cemetery will not be accessible to the public."
It is unclear how long the dumping has been going on, but the council said waste was found "well under the surface".
"This material appears to have been processed and dumped at our cemeteries as part of alleged criminal activities by individuals intent on avoiding landfill charges and for their personal gain."
The council has begun civil proceedings in the High Court against a company named Brixton Tipping Service Ltd, its owner and a former manager who worked for the council.
Brixton Tipping could not be reached for comment.
A council spokesman said the former employee was past retirement age and has since taken his retirement.
The Environment Agency investigation is ongoing, a council spokesman said.
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