Staff at a village school were stunned when three men pulled up in a van and dumped oil drums in the school car park before driving off.
The incident happened at New York Primary School on Friday, during the half term holiday.
Executive headteacher Paul Bargh said: “I was shocked and very disappointed to receive a telephone call on Friday afternoon to inform me that three 40-gallon oil drums and several boxes of car parts had been dumped at the end of the new car park at the school.
“Luckily, two members of staff were at school and witnessed the incident, the van and the three men that were involved. This meant that we could arrange for the toxic, hazardous waste to be cleared before the children returned to school on Monday.
“Unfortunately, we were unable to get the registration of the vehicle. However, we did capture the incident on CCTV and are currently having the images enhanced.”
Mr Bargh added: “This was a despicable act. If members of staff hadn’t been in school on Friday afternoon, preparing classrooms, then the waste would have gone unnoticed until Monday morning when the children returned.
“We were very grateful to East Lindsey District Council’s environmental health department for their quick response and clean up on Saturday.”
A spokesperson for ELDC said: “Any fly-tipping is a blight on the landscape and, as in this case, can be potentially hazardous.
“We take all reports of fly-tipping very seriously and clear the waste away as soon as possible. Our message is that fly-tipping will not be tolerated and we will take the strongest possible action we can against offenders.”
The unmarked Transit van pulled into Mill Lane at 2.52pm on Friday and departed a minute later after the waste had been dumped.
If you have any information about this incident contact the police on 101.