4:55pm: UPDATE: The explosive material found in the Leschnault Estuary has been detonated in the water near the jetty.
There was one loud bang from the explosion and a small cloud of smoke rose from the water.
Old Coast Road has been reopened by police.
4:40pm: UPDATE: Police have confirmed that the explosives will be detonated in the water surrounding the jetty at the Leschenault Estuary rather than on the foreshore as it was safer to than bringing them back to land.
Police have evacuated the area surrounding where the explosives are to be detonated.
4:15pm: UPDATE: Watch video footage from Police Commissioner Karl O'Callaghan's press conference earlier today.
3.30pm: UPDATE: Police have closed Old Coast Road to traffic in the region of the Leschenault Estuary from Laura Avenue to Pratt Road.
It is anticipated that the explosives could be detonated in the next half an hour.
A spokesperson from Cristal Global has confirmed that the company's open day on Sunday has not been cancelled.
2.30pm UPDATE: Authorities involved in this case are hoping to destroy the explosive material in the next two hours during daylight.
While those involved finalise their plan we understand the explosion will happen in the Leschenault Estuary and not on the foreshore as previously thought.
We will continue to update you throughout the afternoon and bring you pictures of the detonation as it happens.
1.30pm: UPDATE: WA Police Commissioner Karl O'Callaghan says protocols for handling suspicious packages will be reviewed, after it emerged that police treated a batch of explosives found in Leschenault Estuary as if they were illicit drugs.
Read more here.
12.17pm UPDATE: Authorities may use a police robot to transport explosive material into a hole on the Leschenault Estuary foreshore before destroying it.
The WA Police robot is fitted with a mechanical arm and a camera and is remote-controlled.
It can also detonate a bomb without any human contact.
Our reporters are standing by to hear the final decision on how and when the explosives will be blown up.
11.30am UPDATE: Authorities will consider three options for the safe detonation of explosives found in the Leschenault Estuary earlier this week.
The Bunbury Mail understands the explosives may be blown up where they were found near the estuary's jetty, at another location underwater or on the banks of the estuary.
Navy personnel are currently digging holes about 50 metres from the estuary's shore where the explosives may be placed before they are detonated.
Reporters are standing by for an updated timeline of when and how the detonation will take place.
Perth press conference
WA Police Commissioner Karl O'Callaghan has said he can't say how long it will take to make the scene safe at Leschenault Estuary near Australind where a second suspect package has been discovered.
The Australian Defence Force is working to make the package safe after it was discovered on Thursday, and Dr O'Callaghan said the forensic exclusion zone around the scene will remain in place until the area was secure.
The exact contents of the second package have not yet been revealed, although Dr O'Callaghan said it is being treated as potentially volatile explosives, like the original package discovered earlier this week.
"We don’t know what is in the package currently at the end of the groyne in the inlet. We haven’t been able to examine it at this stage – we will have to wait on further advice from the ADF who are assisting us with this," he said.
He said Police were still waiting for advice from the ADF about the safest way to dispose of the package, which has so far remained in the water where it was discovered. No details about the package's size or contents have been officially confirmed.
Premier Colin Barnett said public safety was the "first consideration" of those working at the scene. He urged the public to cooperate with police requests.
Navy clearance divers are also working at the scene, and Police would not rule out the possibility of finding further suspicious items in the inlet.
Dr O'Callaghan would not reveal what other federal agencies are present at the scene, saying he would not share details of an ongoing serious crime investigation.
He refused specifically to comment on whether the Australian Security Intelligence Organisation is involved, although he added that the national terrorism threat level has not been raised.
Police have urged anyone with information, particularly among the Australind community, to come forward.
"Somebody must have seen something unusual down there over the last week or two – if they have seen something unusual we need to know about it," Dr O'Callaghan said.
He refused to comment on whether police have so far identified any suspects or motives in connection with the explosives.
Australind press conference - Calling for community information
South West Superintendent Peter Hatch held a press conference at Australind Police station yesterday to urge the community to help with the investigation after volatile chemicals were found submerged under a jetty on Tuesday.
VIDEO: Watch footage from Superintendent Peter Hatch's press conference below.
“We are particularly appealing to anyone who may walk or fish regularly in the area – no information can be discounted,” he said.
“At the end of the day this has been discovered in our backyard, so I would urge the community members from Australind and Bunbury to come forward.
“Any small piece of information that people may think is insignificant could help us solve this mystery.”
“This is particularly relevant for those in Australind, around the estuary or the jetty and groyne area.”
Call Crime Stoppers on 1800 333 000.
