Wildlife officials are scratching their heads after more than 1,000 dead blackbirds fell from the sky this weekend, leaving the roads and lawns of one small Arkansas town littered with their remains.

The Arkansas Game and Fishing Commission said they started hearing reports from Beebe, Ark., at around 11:30 p.m. on New Year's Eve.

Officers estimated that over 1,000 birds fell from the sky before the incident stopped around midnight. In most cases the birds were dead, but some were found clinging to life.

"Shortly after I arrived, there were still birds falling from the sky," said AGFC wildlife officer Robby King in a statement. He collected 65 samples that were sent to be studied by livestock and wildlife health experts.

The birds were found in an area spanning more than 1.5 kilometres and are being cleaned up by a private company. It appears the incident only involved blackbirds.

Karen Rowe, an ornithologist with the AGFC, says it is unclear what killed the birds but it is unlikely they were poisoned.

"Test results usually were inconclusive, but the birds showed physical trauma and that the flock could have been hit by lightning or high-altitude hail," Rowe said.

Rowe said it is possible the birds were startled to death by fireworks being set off to celebrate New Year's Eve.

She said necropsy testing scheduled on Monday will determine if the birds died from trauma or toxin.

This is not the first time the phenomenon of a mass of birds falling dead from the sky has been reported.

Earlier this year, scores of blackbirds fell dead into a front garden in the county of Sommerset, in England.

Similar incidents were reported in Australia in 2008 and 2007, while dozens of birds dropped dead in the streets of Austin, Texas in 2007.

No caused was determined in those cases, although Austin officials felt toxins may have been the cause.