Fly-tippers have again used Epping Forest as a dumping ground.
A sofa, mattress, paint, wood and other building materials were discovered yesterday in a car park in Woodridden Hill, near High Beech.
Forest Keepers are now assessing the contents of the waste to see if there are any clues as to who is responsible.
The City of London Corporation is offering a reward of £500 to anyone who gives evidence that leads to a successful prosecution.
The corporation records around 730 fly-tip incidents every year, recent examples of which have included asbestos, cannabis plants a dead donkey and a toy panther.