Alleged terrorist plot mastermind researched explosives, Perth police say

A 22-year-old Perth man has been charged with allegedly preparing for a terrorist attack.

The man, who is expected to appear in court today, was initially arrested and charged with nine offences in December.

But following further investigations by Western Australia's Joint Counter Terrorism Team, he has now been charged with one count of "acts done in preparation for, or planning, terrorist act".

Police allege the man sought help on a messaging platform about "explosive devices, military and tactical training, education, weapons manufacturing, combat techniques and fake documents" as part of planning for a terrorist attack.