Hostages caught in Sydney's siege have revealed how some of them managed to escape when the gunman's back was turned.

Haron Monis was known to authorities for a string of offences.

Some hostages held in the Sydney cafe may have had thoughts of attacking the hostage takers as survival instincts "come to the fore", a psychologist says.

The MP who chaired the anti-terrorist legislation rushed through Parliament last week, MarkMitchell, says the bill was "100 per cent" justified.

Father-of-four Craig Stoker had just bought a coffee at the Lindt Chocolat Cafe in Sydney's Martin Place when he walked out and bumped into a "crazy-eyed" man.

A New Zealander who saw the Sydney siege unfold has described seeing people cowering on their knees only moments after a gunman took them hostage.

The country’s highest Islamic office holder has condemned the actions of a gunman responsible for a hostage situation in Sydney’s CBD.

Could it happen here? That is a question to haunt this country whatever the outcome of the hostage crisis in Sydney.

Here's what we know now about the situation in Sydney where a gunman has seized hostages.

Read how the Sydney siege unfolded during the day.

New Zealanders caught up in the area where a hostage drama is unfolding in central Sydney - some who are still in lock down - have spoken about their experiences.

The cafe siege in Sydney was only to be expected after Islamic State urged followers to launch such “lone wolf” attacks, specifically mentioning Australia, terror experts say.

Martin Place in Sydney CBD is in lockdown after gunmen took hostages at the popular Lindt cafe this morning.

Parliament has just passed legislation aimed at stopping would-be foreign fighters from leaving New Zealand to join Islamic State in Iraq.

Thirty-five people were killed and 150 injured when multiple explosions tore through the central mosque in Kano, police said.

The Government is legislating at breakneck pace to pass a bill it calls "Countering Terrorist Fighters Legislation".

Michael Adebowale made no attempt to hide his rage or his thirst for revenge in his online conversation with a jihadi leader in Yemen.

Only in a topsy-turvy world would it be seen as rational to bring a posse of spies to heel by increasing their rights to snoop without a warrant, writes Brian Rudman.

The Government's controversial "foreign fighters" legislation allowing the recall of suspected New Zealand jihadists' passports and warrantless surveillance is set to pass its first reading.

The British Isis killer known as "Jihadi John" may have a body double, according to a new video analysis.

Urgent law changes being introduced to combat the threat of "foreign fighters" will be in place until 2018, as opponents question their 'short-term' nature.

Urgent changes to the law introduced to combat the threat of "foreign fighters" had been flagged by the Prime Minister as for short-term only.

We've had reports of abuse by Kiwis who think all Muslims are terrorists. I say to those responsible: when you scream at them as you drive by, you are terrifying them.

Much has changed in Iraq and Syria in the six weeks since the last Western hostage, Alan Henning, was beheaded.