Police received the first report of an offensive letter from a property owner at Dubbo last Tuesday, November 19.

Police received reports a typed letter of a similar nature had been received by a property owner at Walgett on Tuesday, as well as another by a property owner at Peak Hill.

Each of the letters refer to the current prolonged drought conditions and make suggestions to the victims that they should take the lives of themselves and their livestock.

Initial inquiries indicate the letters are being hand-delivered to mailboxes.

Inquiries continue, and police urge victims to photograph and preserve the letters and envelopes before making a report to your local police station.

NSW Police Force Rural Crime Prevention Team State Coordinator, Detective Inspector Cameron Whiteside, has labelled the letters as disturbing, adding unnecessary stress to landholders.

"This is downright disgraceful," Det Insp Whiteside said.

"It is extremely important that these letters are not over-handled, both in a physical sense and by not disclosing information to fellow members of the public which may impact the investigation.

"Victims should report the matter to local police in a very timely manner in order to increase our chances of resolving the nature of these letters.

"Anyone who has received a similar letter is encouraged to contact their local police station and report the matter."