The man who took up to 20 people hostage in a Sydney cafe has been named as Iranian refugee Man Haron Monis, aged 50.
Sydney police said the self-styled Sheikh - who raised a flag with the Islamic declaration of faith in Arabic written on it and placed human shields in the window before police officers moved into the building - was well-known to them.
It was later revealed he had died in the confrontation with police after shooting one of his hostages.
Channel Nine reporter Airlie Walsh told Sky News charges against him included accessory to murder and sexual assault.
"The list of charges against the Sheikh are extremely long and extremely worrying," she said.
He is believed to be currently on bail for 47 sexual assaults he is accused of carrying out while operating as a spiritual healer.
Monis moved to Australia in 1996 from Iran. The country's foreign ministry said his actions were "not in any way justifiable".
He is notorious in Australia for sending abusive letters to family members of soldiers killed in Afghanistan and was sentenced to 300 hours of community service for his campaign.
Among those targeted in his hate mail was the widow of Sergeant Brett Till, who was killed while defusing a bomb on 12 March 2009.
At the time of the conviction, Bree Till said: "We sat reading these letters (which) made out to be something supportive but then the juxtaposition of this man accusing my husband of being a child-killer while dictating how I should raise my children. It was scary."
Last year, Monis said last year that he wanted to send a "very nice condolence letter" and 237 baskets of flowers to the families of British soldiers killed in Afghanistan but failed to overturn a court order banning him from using the postal service to contact relatives of military personnel.
He was later charged with being an accessory in the murder of his ex-wife.
Monis operated a website which was taken down shortly after he was named as the hostage-taker in the media.
In a letter on the site, which he signed Sheikh Haron, he accused the US, Britain and Australia of "oppression and terrorism" alongside images of dead children.
He also called for non-violent activism.
"Islam is the religion of peace and a Muslim should be a peace activist," Monis wrote.
"Islam is against oppression and any unfair violence. Islam is against terrorism. As I have repeatedly said earlier: 'this pen is my gun and these words are my bullets, I fight by these weapons against oppression to promote peace'."
Monis - who reported asked for an Islamic State flag as part of his demands - converted from Shia to Sunni Islam, according to his website.
"I used to be a rafidi, but not anymore. Now I am a Muslim, Alhamdu Lillah," he said, using a hardline jihadist word for a follower of the Shia branch of Islam.
Sky's foreign affairs editor Sam Kiley said Monis may have a "fetish for self-publicity" which could have proved "useful to the hostage negotiators".
He added that Monis was a "fantasist" with a "really very chaotic background".
His former lawyer Manny Condits said he believed that Monis was acting alone.
"This is a one-off random individual. It's not a concerted terrorism event or act. It's a damaged goods individual who's done something outrageous," he said.
"His ideology is just so strong and so powerful that it clouds his vision for common sense and objectiveness."