Victoria Police in Ballarat are conducting a targeted search operation for missing woman Samantha Murphy.

A phone and 'items of interest' have been discovered in farmland near where Murphy's phone last pinged in February.

Crime scene officers and sniffer dogs are involved in the search, with the area cordoned off for forensic testing.

Patrick Stephenson, charged with Murphy's murder, remains silent on her whereabouts and is believed to have acted alone.

Hundreds of community volunteers are actively participating in the search for Murphy's body.

Stephenson is in custody and set to appear in court in August as the investigation continues.

The public is advised to avoid the search area, with more details expected to be released as the search progresses.