Bee kill-off in local parking lot blamed on pesticides, raising bigger questions about colony collapse disorder

LONDON, ENGLAND - JUNE 29: Beekeeper and Chairman of The London Beekeepers Association John Chapple installs a new bee hive on an urban rooftop garden in Hackney on June 29, 2009 in London, England. It is estimated that honeybee numbers in the UK have fallen between ten and 15 per cent in the last two years. (Photo by Dan Kitwood/Getty Images)

Bees are dying at an alarming rate that experts warn will do serious damage to the global food supply. And now, someone accidentally killed thousands more.

At least 25,000 dead bees fell from trees and littered the ground of a Target parking lot in Oregon, the Los Angeles Times reported. Mostly bumblebees were killed in what experts say is the largest known die-off of bees in the United States.

State officials say the Safari pesticide is to blame. Some person or organization had sprayed Safari on trees in the parking lot, though officials have not identified who is responsible.“It was a mistake to put it on linden trees in bloom,” Dan Hilburn, director of plant programs with the Oregon State Department of Agriculture, told the LA Times.

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Since 2006, 40 percent of the bee colonies in the US have collapsed. But the United States government and the biotech industry are reluctant to blame pesticides.

Earlier this year, Europe's lead food safety agency made a landmark announcement about neonicotinoid, the world's most widely used insecticide. The European Food Safety Authority concluded that the chemical posed an "unacceptable" danger to bees.

The chemical's manufacturer, Bayer, has continued to defend its insecticide. Instead, Bayer has  blamed other factors on bee deaths.