As forensic evidence against the killer mounts, police expressed frustration yesterday.

''Someone in the community must know what's occurred, be it a relative or a friend or close companion,'' Sergeant Ian Dodds of Tumbarumba police said. ''I'm sure it is playing on their conscience because they are concealing a serious offence.''

As many as 200 wild horses have been killed in the Maragle and Bago State forests in the past 18 months.

Police say the gunman, who may have accomplices, is shooting at wild horses ''indiscriminately'' with an unlicensed high-powered rifle.

The offence carries a jail sentence and fines.

The spate of shootings has split the community between horse lovers, who want the brumbies protected, and conservationists who advocate culling.

Brumbies are not classified as pests. It is a crime to shoot them, or have them shot, without prior notification to Forests NSW.

Sharyn Townsend, who is trying to save the horses, said the Government should create a reserve.

''This is not going to stop unless someone steps in,'' Ms Townsend said. ''As soon as the pressure dies off, the horses get shot again. They're being decimated. You've got a tourism attraction here and the Government has to save it. Brumbies have been running wild in the hills for 200 years. It's part of our heritage that's coming close to being lost.''

The Federal Government said yesterday the management of wild horses in state parks was a matter for the states.

Forensic evidence taken from the carcasses in the latest shootings at Christmas with the help of the Game Council NSW would help track the killer, Sergeant Dodds said.