Investigators have ruled out bird flu as the cause of death of hundreds of starlings on Anglesey.
The birds were found dead on a road earlier this month.
Preliminary tests by Defra found that tests for bird flu came back negative and indicated death from trauma and internal bleeding due to impact with the ground.
It said it was working closely with the North Wales Police Rural Crime Team to collect more information about the incident.
Hannah Stevens, who found the birds on the ''unclassified road'' on the island, said she had seen the "massive flock" flying overhead before landing and appearing to eat something in the road.
The birds were initially sent away for toxicology tests and a postmortem to determine how they died. Police are also looking in to whether this is the second time hundreds of birds have died all together in exactly the same place.