'Remotely detonated bomb' killed New South Wales man John Burrows

Exactly two years after John Burrows was killed by an explosion at his mother's New South Wales home, police have revealed they believe the bomb was remotely detonated.

The 58-year-old greyhound trainer was killed by an improvised explosive device (IED) as he walked towards his mother's garage in the tiny village of Portland about 6.30am on July 24, 2015.

Police found the remains of the IED outside the garage. It had been concealed under a cardboard box.

Today, police said investigations had them to believe that the bomb was detonated using a radio-controlled receiver, which was likely "sourced by someone in the Portland community".

The type of receiver is found inside model planes and helicopters, and has only been available since May 2013.

Detective Chief Inspector Luke Rankin appealed for public help to progress the investigation.

"We are particularly interested in speaking to retailers or people in the Portland area who may have sold an item - on social media sites, garage sales or even disposed of at a local tip - matching the description of the radio-controlled receiver," he said.