Pictures have emerged of the 20-year-old man accused of documenting plans to commit mass casualty terror attacks at WA Parliament, police headquarters and religious places of worship.

Police say Jayson Joseph Michaels had come to their attention last month — as part of an encrypted messaging group chat on Telegram — where he allegedly expressed anti-Semitic and racist ideologies with other like-minded individuals.

He was living with his parents at their Bindoon property, more than 80km north east of Perth, when investigators from the WA Joint Counter Terrorism Team executed a search warrant on Thursday afternoon.

Police said they seized seven rifles, a ballistic vest, multiple knives, a gas mask and lock-picking tools.

They also said they found a notebook, which allegedly outlined preparations for a terrorist attack on police headquarters, Parliament House and places of Muslim faith in WA.

Last year, a former employer at a gravel and sand supply business shared a photo of Mr Michaels in high-vis work gear, celebrating his efforts on the job.

“This young fella reached out to me for employment recently,” the post said.

“Jayson is a little unsure on what his career pathway looks like though asked to have a crack with our crew.

“Deadset had no idea the first day. What a week can do . . . make or break.

“There are many things I love about running a small business and one of them is mentoring these young fellas.

“Well done cobb.”

The West has also obtained an image of Mr Michaels as an young school boy smiling as he holds a school certificate.

Mr Michaels’ digital footprint appears limited after his arrest.

It is understood at least one of Mr Michaels’ relatives legally owned firearms.

WA police commissioner Col Blanch, when initially briefing the public after the arrest, said all the firearms seized were legally obtained and had gone through the transition process for the new firearms laws.

Police said they were unaware of Mr Michaels’ alleged plot until they searched his parents’ property and discovered the notebook.

Mr Blanch said police were examining his digital devices and would also be looking closely at Mr Michaels’ inner circle.

Mr Blanch stated Mr Michaels was not previously known to police.

“(Director-General) Mike Burgess from ASIO was very clear some years ago now that young lonely men need care and love and support and friends and purpose in life, or they find people online to exploit their feelings, and they go down the wrong pathway,” he said.

“We use the phrase self-radicalisation, but there’s often predators online who are seeking to change their perspectives from being and living in a wonderful State like WA into hating others, and that’s the first thing we should all do to try to prevent.”

Mr Blanch said other Australians and people overseas were in the same encrypted chat that led police to Mr Michaels.

“All we can see is a group of like-minded (people) . . . talking about their hate for other people in our community, again, the least Australian thing you could ever do,” he said.

“So our focus at the moment is to understand who’s on that message group, but early indications are there’s no hierarchy, there’s no structure, there’s no organisation.”

On Friday, Mr Blanch said police would much rather intervene and assist allegedly radicalised individuals instead of having to make an arrest.

“I think it pains every police force that we have to arrest these people in the community because they’ve been radicalised online — I would much rather they got help years ago,” he said.