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.

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.

A flurry of loud bangs erupted just after 4am NZ time as a swarm of heavily armed police stormed a downtown Sydney cafe where a gunman had taken hostages.

As the Sydney siege threatens to open up old prejudices, hashtag #illridewithyou has led a call for unity.

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.

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.

US embassies have been told to prepare for violent protests ahead of a report into the CIA's use of torture.

The father of a teenager from Cardiff is thought to be the first Briton to have rescued his son from the jihadist group Islamic State.

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".

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.

The Islamic State militant known as Jihadi John has threatened to bring slaughter to the streets of Britain and the West in a new video announcing the murder of an American aid worker.

UK has received reports that notorious terrorist accused of killing two British hostages has been injured in an airstrike.

Four brothers slipped out of Australia last week to join the fight with Islamic State (Isis) in Syria.

The former US Navy Seal who claims to have shot dead Osama bin Laden has gone from "hero to zero" and "put a bullseye on his back" after coming forward to take the glory for the killing.