A variant of the IS flag. Ms Kay was one of several people contacted that afternoon, and she was only too willing to help. "A lot of people in the Muslim community were devastated," she says. "We were ready to jump – 'just say how high' – to help police prevent a tragedy." Ms Kay believes she called as many as 50 people, but finding an IS flag – or anyone willing to admit they had one – proved no easy task. And soon her contacts started asking: "Are we being set up?"

"They were very suspicious," she says. "Some accused me of being an informant." But she counselled that they should try to help. And the officer kept calling back, "three or four times over the next hour to see if I had got an Islamic State flag or not. There was a sense of urgency that I get it and that I take it down to Bankstown police station, and they were going to put it in a patrol car, with the lights [flashing], and bring it to the city." Monis's hostages recited his demands on Facebook and YouTube, as police worked to have them taken down. Hostage Julie Taylor, a barrister, said he would free five hostages if Prime Minister Tony Abbott called him to record a short conversation to be played on air. He would release two if the politicians told "the truth, which is that this is an attack by Islamic State against Australia". And he would allow one to go if the flag were delivered. In the end, Ms Kay says, police sourced their own flag. But then they told her it had been decided there would be no trade with Monis in any case.

By now she had burnt many bridges in her own community. It got worse. About 2am the next morning – about the time of the deadly final shootout inside the Lindt cafe – NSW Police searched the western Sydney home of one of the young men she had contacted. He had considered handing over his flag to Ms Kay but then thought, no, it was a trap. "And so he then believed I did try to set him up," she says. The next morning, she was told, the Australian Federal Police raided the homes of another two men who had been contacted during the community's urgent attempt to help save hostages. "Obviously, they were listening to all our phone calls," Ms Kay says.

"I want to be able to have dealings with police … but when it gets thrown back in your face, it sets us back two steps." Lawyer Zali Burrows, who represents some of the people who tried to help police, wonders: "Why didn't they just print one out?" A laser printer could have produced the flag on cloth and they could have delivered it in half an hour, she says. Lydia Shelly, a solicitor from the Muslim Legal Network, says: "Our overriding concern was with the safety of those innocent Australians being held against their will." Police would not respond to questions about the flag or whether they intended to allow Monis to display it to the world's televisions and risk him winning the support of other extremists.

Ms Kay says there is nothing sinister about the flag that Islamic State has misappropriated. It depicts the prophet's seal and "it's a flag that Muslims should have. It's not our fault that these barbarians have taken it as their flag." She says she would want to help police in another such crisis, but: "They're not building trust. With this incident they have not built trust at all. Loading "You don't understand the pressure cooker we're in and the interference that the AFP and ASIO have, and the fear that they create, and how they stalk – and I can say stalk with confidence – members of our community and instil fear in their families and ostracise them from their workplace and the people they know, so they become paranoid and they don't interact with anyone. "This is the kind of norm they've created here, where no one trusts anyone any more."