Around 100 birds were found lying dead on a snow-covered street in southern Sweden’s Falkoping, after a string of unexplained animal deaths hit the U.S. and New Zealand, Swedish newspaper Aftonbladet reported Wednesday.
Local veterinarian Robert ter Horst speculated that the birds had fallen from the sky after being frightened by fireworks set off late Tuesday.
However, the cause of the jackdaws' deaths was disputed after a truck driver claimed he was responsible.
Christer Olofosson, a rescue services worker, said the truck driver claimed he saw about 70 live birds on the road Tuesday, adding, "he ran over the lot of them and did not think it was a big deal, but realized today [Wednesday] that it attracted attention, not only in the Swedish media, but also abroad."
Police told the newspaper the majority of the jackdaws involved were not "physically damaged," which would contradicted the truck driver's account of events.
Horst, who sent the dead birds to Sweden's National Veterinary Institute for analysis, said the driver's theory was "possible," but further examination of the birds was needed before a cause of death could be established.
The Falkoping incident came after a string of unexplained animal deaths in the U.S. and New Zealand.
Some 500 dead birds were found next to a highway northwest of Baton Rouge, La., Monday, littering a quarter-mile stretch of road. The birds were sent to laboratories for testing, and no cause of death was immediately known.
The carcasses included starlings and blackbirds, the latter the same as the nearly 5,000 birds that plunged to the ground in Beebe, Ark., on New Year's Eve.
The mysterious deaths of 100,000 drum fish about 125 miles away were thought to be unrelated.
Similarly, no explanation was reached on the Coromandel Peninsula in New Zealand, where vacationers were shocked when hundreds of dead fish washed ashore