A bomb-disposal robot has been used by West Australian police to detonate what they suspect could be deadly chemical explosive TATP underwater in an estuary south of Perth.
The controlled explosion near a jetty south of Perth, coordinated by police and the armed forces, was carried out after navy divers spent the day searching for clues in the Leschenault estuary.
The explosive - widely used by terrorist organisations in recent years - was discovered earlier this week in Australind, south of Perth. A second package also suspected to be TATP was the one detonated late on Friday, 36 hours after it was found.
The robot had been seen working close to the shoreline before the package was spectacularly blown up in the water.
Security around a regional foreign ministers meeting in Perth was reassessed, while WA police commissioner Karl O'Callaghan revealed one officer had been injured during the initial find.
Mr O'Callaghan had already said the public was not in danger despite a wide exclusion zone around the jetty and a heavy police and defence force presence.
Police had initially believed the crystalline substance found by a member of the public on Tuesday night was for making drugs, and so was transported to Perth to be stored in the major crime headquarters in the CBD.
But when the nature of the substance was discovered, buildings were evacuated and the explosives were delicately transported before controlled detonations at a Perth racetrack.
The Commissioner said an officer suffered a chemical burn when initially handling the material and WA police protocols on how to handle drugs and chemicals would be reviewed.
"Officer safety is a primary concern for me and we will certainly be reviewing the protocols as a result of this incident," Mr O'Callaghan said.
The police union said they had massive concerns about the testing regime for chemicals being discovered by police across the state.
"We're very keen to make sure that things are put in place to make sure this doesn't happen again, said acting president Brandon Shortland.
"I would be saying as a starting point that any significant amount of any chemical, whether they think it's drugs or not, is tested on scene by the chemistry centre of WA."
Federal investigators are still involved in the inquiry, but it has not been confirmed whether ASIO is involved.
The national terrorism alert level has not changed.
TATP is highly volatile and can be manufactured from household ingredients and is known as "Mother of Satan".It's believed three kilograms of the chemical was found at Australind. Each of the explosives in the 2005 London bombings weighed at least 2.5kg.