The Te Awamutu Warehouse carpark was a sparrow graveyard after the birds were believed to have been poisoned.
Bodies of dead sparrows lay scattered as far as ASB Bank and the Courier office.
Members of the public discovered the dead sparrows underneath two large oak trees in the carpark - the sparrows' usual roosting spot.
Te Awamutu woman Lee-Anne McKee suspects someone poisoned the sparrows because they were sick of bird poo on their car.
"If you park your car under the oak trees then it will get covered in bird poo.