Murder charges after man's body found beside highway

Officers negotiated with the armed man before he was arrested around 11pm and taken to hospital.

Homicide Squad detectives interviewed the man before charging him with murder in connection to the death of a man found beside the Henty Highway near Finlayson Road.

The elderly man, believed to be about 80 but not yet formally identified, was discovered with serious injuries about 9.15am on Monday.

"I was briefed in relation to a deceased person that was located in the western district, a male on the side of the road who (had) serious injuries," Deputy Commissioner Bob Hill told reporters on Monday.

The 49-year-old man, from Minyip, will appear at Horsham Magistrates' Court on Wednesday.