Fifty emergency services personnel and local volunteers are involved in the search effort, including police watercraft and aircraft, the Australian Maritime Safety Authority jet and Department of Fisheries boats. Authorities are also scouring through CCTV footage as well as beaches and sand dunes.
WA Police Inspector Alyson Brett said nine police divers have been out targeting some of the areas where they know Mr Phillips usually dives.
"He's very, very experienced and we're very, very hopeful that we will find him safely," she said.
Mr Phillips friend Adrian confirmed his extensive diving experience stating that he has spent a lot of time in the water.
“He’s done some of the toughest fishing you’ll ever see in your life. Long haul line fishing, diving, scuba diving…”
Mr Phillips is described as about 182 centimetres tall, bald with blue eyes.
Police ask anyone with information to contact them immediately on 131 444.
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