Report on Sydney cafe siege gunman due this month

Report investigates how 50-year-old Monis, was able to take staff and customers at the Lindt cafe hostage in December

SYDNEY: The Iranian-born gunman who took 17 people hostage in a Sydney cafe had "taken advantage of our system", Australian Prime Minister Tony Abbott said Wednesday, saying he had received an official report into the tragedy.

The report investigates how 50-year-old Man Haron Monis, who had a history of violence and extremism, was able to take staff and customers at the Lindt chocolate cafe in Martin Place hostage in December.

Monis, a self-styled Islamic cleric, was on bail for various charges at the time of the siege in which he and two hostages died, including sexual offences and abetting the murder of his ex-wife.

"Plainly the Martin Place murderer took advantage of our system -- that's what this report is designed to expose to us, and we will take the strongest possible action to ensure that this can't happen again," Abbott said.

"And I'm determined to learn those lessons and assimilate them into policy because the first priority of government... is to keep our country safe and plainly our country wasn't safe on that dreadful day in Martin Place just before Christmas."

A coronial inquest is looking at what occurred inside the cafe, including how two hostages died -- cafe manager Tori Johnson and barrister and mother-of-three Katrina Dawson.

The government report investigates Monis's background, and is expected to detail how he was given refugee status and welfare benefits.

Abbott said he expected to release the report, along with the government's response to it, by the end of the month.

The coronial inquiry which opened last week heard that Monis shot Johnson, 34, in the back of the head moments after several hostages had escaped in the early hours of December 16.

The killing led to the order for police to storm the cafe and Dawson, 38, was struck by six fragments of a police bullet or bullets which ricocheted from hard surfaces into her body, it heard.

Work is underway to reopen the Lindt cafe, which has been boarded up since the incident, with reports saying it will have a permanent tribute to the victims. A decision on when the cafe will reopen is expected next week.

"There will be a tribute, a plaque or something," an unnamed Lindt employee told Australian Associated Press.