With a gun pointed at him, Lindt Cafe manager Tori Johnson was forced to read a handwritten note scrawled on a piece of A4 paper saying Australia was under attack from Islamic State and that bombs were placed around the Sydney CBD.

The inquest into the December 2014 siege in Sydney’s Martin Place heard gunman Man Haron Monis likely planned his attack for months, that he may have had an accomplice and possibly had hopes of escape.

It also emerged on Monday that Monis had demanded to debate then Prime Minister Tony Abbott live on radio, and that three bombs would be exploded if police approached him or “other brothers”.

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The triple-zero call made by Johnson, part of which was played on Monday, also reveals a chaotic initial contact with police.

The 12-minute call, made at 9.41am, begins with: “I’m calling from Martin Place. I have a message to read to you.”

But Johnson is frequently interrupted by the operator who doesn’t know where Martin Place is, and is unfamiliar with the streets in the area.

“There is more message that I have to read to you as well,” he continues.

Operator: “Alright, well you just need to hang on a second.”

It was about this time, five minutes into the call, that Monis produces a shotgun from a large blue Big W bag.

Johnson: “I need to finish reading this …”

Operator: “Yes, I understand that. Just hang on a minute.”

Johnson: “I have a gun in front of me.”

Operator: “Ok”.

The note, which Johnson was eventually able to read out in full, announced that “Australia is under attack by Islamic State”.

Escaped hostages run with their hands up from the Lindt Cafe during the siege. Photo: Getty

“There are three bombs in three different locations: Martin Place, Circular Quay and George Street,” it said.

“I want to contact other brothers and ask them not to explode the other two bombs but I can’t contact because they don’t carry phones with them.

“The plan is to request Tony Abbott to call them or me and to have a debate while it is broadcast live on ABC national radio.”

Counsel assisting the Coroner, Jeremy Gormly SC praised the actions of Johnson, and his calm manner.

“One cannot help but admire the calmness and coolness with which he managed that call,” Mr Gormly said.

Johnson was fatally shot by Monis, who was killed when police stormed the Martin Place building 17 hours after the siege began on December 15, 2014.

But it appears Monis had actually hoped to escape, and that he had planned the attack for months, with Mr Gormly telling the hearing the gunman had acquired a mobile phone registered in another person’s name on October 15, 2014.

Monis did not use the phone until the day of the siege.

“Assuming Monis acquired the mobile using a false name, that could suggest that he had the siege in mind as far back as October 2014,” Mr Gormly said.

“The fact that Monis had a different mobile and was seemingly protective of his identity raised the possibility that he had some intent or hope of escape and evasion from police.”

The inquest was shown CCTV footage of Monis walking through Martin Place on the morning of the siege, but police have not been able to establish how he made his way into the city from his home in western Sydney.

“It’s entirely possible Monis was driven into the city and dropped off, though investigations continue as to who provided that assistance”, Mr Gormly said.

The inquest continues.

– AAP