An American Islamic State jihadist accused of enticing Australian teenager Jake Bilardi to travel from Melbourne to the Middle-East and blow himself up in a suicide attack in Iraq is locked up in a New York jail.
Mirsad Kandic, 36, was a New York resident with an alleged longtime desire to engage in jihad against the US military.
Prosecutors said Kandic managed to leave the US for the Middle-East in 2013 despite being on the US government's no-fly list and became a key member of IS's "media department".
He allegedly used more than 100 Twitter accounts to recruit foreign fighters and publicise IS attacks and territorial gains.
The grand jury indictment and other court documents against Kandic made public on Wednesday largely focus on Kandic's relationship with Bilardi, a shy, lonely Australian 18-year-old who fell under the spell of IS.
"The defendant encouraged Bilardi to commit violent attacks including suicide attacks," the US government's detention memorandum submitted to the District Court in New York states.
Prosecutors allege Kandic helped Bilardi to fly from Melbourne to Turkey in August, 2014, and via Twitter sent messages instructing the teenager to stand in a particular part of the Istanbul airport and wait for someone to meet him.
From Turkey, Bilardi travelled to IS-controlled areas of Syria and Iraq.
"The defendant continued his contact with Bilardi in the ensuing months as Bilardi fought on behalf of ISIS in Iraq," prosecutors alleged.
In December 2014 when Bilardi informed Kandic he intended to become an "istishhadi", or suicide bomber, Kandic supported the mission and replied: "Level these kufar (non-believers)", prosecutors alleged.
In March 2015 via Twitter Kandic allegedly asked Bilardi how he felt about his suicide mission.
When Bilardi replied he anticipated his mission would take place in two to three days Kandic allegedly responded with a smiley-face emoticon.
Prosecutors said Bilardi carried out a suicide truck bombing a few days later in the vicinity of Ramadi, Iraq, and according to media reports at least 17 people were killed.
Later that same day Kandic allegedly praised the attack with the Twitter message: "Australian citizen Jake Bilardi aka Abu Abdullah carried the martyrdom operation in #Ramadi, #Iraq. Ask about Abu Abdullah Australi (#JakeBilardi) they will tell you he was a sound brother, Took part in many battl(es)".
"Just prior to Bilardi successfully detonating a suicide bomb in Ramadi, Kandic told Bilardi he hoped Bilardi's victims' organs would 'implode', and just after the attack, Kandic publicised it on Twitter," FBI Assistant Director-in-Charge William Sweeney said.
"Kandic is now back in New York, no longer living freely among us, but rather in federal custody to face justice."
In January 2017 Kandic relocated from the Middle-East to Bosnia, but was arrested in June and extradited to New York on Tuesday.
He has been charged with counts including providing material support and resources to IS resulting in death.
If convicted he faces a maximum sentence of life in prison.