Poisoning is believed to be the cause of death of more than 150 protected native birds, including a large number of wedge-tailed eagles found at Violet Town in August.
Authorities have confirmed an agricultural chemical used for controlling mites was found in six of the carcasses of more than 150 native birds of prey found at a property north of Violet Town in August.
Department of Environment, Land Water and Planning acting program manager compliance operations Andrew Dean said more line searches conducted near Violet Town last week and at Shepparton East and Goomalibee near Benalla in late September, resulted in an additional 47 native birds, including 25 wedge-tailed eagles being found, bringing the total number to almost 200.
"It remains unclear if these birds were deliberately poisoned, however given the large number of birds found nearby, it’s a possibility," Mr Dean said.
He said investigations are continuing and called on community members to report information to Crime Stoppers on 1800 333 000.
More to come.