New York, Stockholm: The mysterious incident of birds falling from the sky has gone beyond United States now. Dozens of jackdaws were found dead in Sweden after several cases in Kentucky and Louisiana.
Five of the dead jackdaws found in the city of Falkoping were being tested.
Earlier about 450 black birds and starlings were found dead in Louisiana - after apparently falling dead from the sky.
The Louisiana bird die-off came just a few days after 5,000 blackbirds dropped dead in neighbouring Arkansas.
Several dozen blackbirds were also found scattered around the yard of a Kentucky resident.
In the US, New Year's Eve fireworks were blamed in Arkansas for killing thousands of blackbirds, and a few days later power lines likely killed about 450 birds in Louisiana.