A Melbourne teen who had started building a bomb similar to the one used in the Boston marathon terror attack was under the influence of an Islamic State recruiter, a court has heard.
The 18-year-old allegedly wanted to burn all non-Muslims and had exchanged numerous messages with UK jihadist Junaid Hussein in the lead-up to his arrest in a counter-terror raid in May last year.
Hussein was a party to a planned terror attack in London in 2013 and is believed to have been killed in Syria in August last year, crown prosecutors told the court.
The defence barrister for the teen - who was 17 at the time of his offending - told the court his client was "infatuated" and "seduced" by an older man who was effectively a "professional recruiter for ISIS".
The teenager, who cannot be named for legal reasons, has pleaded guilty to one count of obtaining documents relating to an improvised explosive device and partially constructing an IED in preparation for a terror act.
In a pre-sentence hearing on Monday, the teen's barrister said Hussein "provided a good deal of encouragement".
"The prisoner was effectively infatuated with the man. He admired him as a great leader," the barrister said.
"It is difficult to exclude it as a relevant factor when one considers the seduction of a child."
Prosecutors said the teen had made a number of Facebook posts about his hatred of non-Muslims, calling them "cockroaches" and "the scum of the earth".
"I want to burn every one of them," the teen said.
Police seized three elbow-shaped steel pipes with end caps attached, a container of pink powder made from the ground heads of matches and sugar, a pressure cooker, Christmas tree lights and other items from the teen's home during the May 2015 raids.
An undated, partially completed passport application was also found.
Prosecutors said the partially constructed pipe bomb had the same components as the improvised explosive devices used in the Boston marathon bombing.
The items were also consistent with photos found in encrypted documents entitled "Make a Bomb in the Kitchen of your Mom", and "Pressure Cooker Backpack Bomb with Switch Detonator", the crown said.
The password protecting the documents' encryption was Arabic for "Islamic State Forever".
The document "Make a Bomb in the Kitchen of Your Mom", was from a 2010 edition of the al-Qaeda magazine Inspire.
It included instructions on "how to make a bomb to injure the enemy" and said it would only take a few days to build a bomb that could kill 10 people.
The teen's defence barrister said the pipes were only three inches in total, one inch each side of the "bend".
"It might be an exaggeration to claim they would damage or cause death to a large number of people," the defence barrister said.
He said the the match-head mixture was not what was used in the Boston marathon device.
The hearing continues.