BEEBE, Ark. (AP) -- Preliminary lab results show the blackbirds that fell from the sky in central Arkansas died from blunt force trauma.
That supports the theory that fireworks on New Year's Eve spooked the birds and sent them flying into cars, houses and each other and plummeting to their deaths.
The Wildlife Health Center in Madison, Wis., released the results Wednesday.
Arkansas' Game and Fish Commission says the birds didn't test positive for any pesticides. Officials are still awaiting lab results from tests for other toxins and infectious diseases.
In all, up to 5,000 birds rained onto rooftops and into fields in the central Arkansas town of Beebe. One struck a woman walking her dog and another hit a police cruiser.
And just four days after thousands of dead blackbirds are found in Arkansas, residents in Sweden are cleaning up their own version of the unusual happening.
Officials in Sweden say about 50 birds were found in the southern Sweden city of Falkoping Wednesday morning.
Wednesday afternoon, test results from the U.S. Geological Survey's National Wildlife Health Center in Madison, Wisconsin confirmed the cause of the birds' death in Beebe was blunt force trauma. This supports the preliminary findings which were released Monday.
Are there any similiarities in the mysterious cases of the birds? Yes. In both the Arkansas and the Sweden cases, fireworks were shot off shortly before the birds were found. Another similiarity? The weather. New Year's Eve in Arkansas was humid and cold. Currently in Sweden, it's very humid and near 30 degrees.
Jackdaws were the type found in Sweden this week. In Arkansas and Louisiana, the birds included grackles, starlings, brown-headed cowbirds, and red-winged blackbirds.
Necropsies of the bird carcases are still being conducted on the most recent findings, in addition to the birds from New Year's Eve in Beebe. It can take up to three weeks to determine the official cause of the deaths.
Nancy Ledbetter with the Arkansas Game and Fish Commission says there is no new development surrounding the thousands of dead fish found earlier this week along the banks of the Arkansas River.