Sydney Siege: Police Send Message To Captives

A gunman who claims to have four bombs is holding up to 20 people hostage in complete darkness at a cafe in Sydney's financial district.

Chilling footage has emerged of a female hostage apparently trying to communicate with police by miming her throat being cut - while news channels have chosen not to broadcast a video of another hostage relaying the assailant's demands.

Witnesses described seeing the hostages looking "exhausted" and "absolutely petrified".

But as night fell and the siege entered its 16th hour, the gunman, who has been named as Sheikh Man Haron Monis , turned off the lights, making it difficult to see what is going on inside the cafe.

Up to 100 armed police are at the scene while negotiators talk to the hostage taker.

New South Wales Police commissioner Andrew Scipione had this message for those inside: "Rest assured we are doing all we can to set you free. We will be looking after your safety as our number one priority."

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The siege began at 10am (local time) when Monis - who was previously known to both Sydney police and media - entered the Lindt cafe in Martin Place carrying a pump-action shotgun.

Shortly afterwards, hostages were seen holding a black flag with white Arabic text similar to those displayed by Islamic State.

Footage showed Monis apparently using one hostage as a human shield.

Channel Ten spoke to two hostages who said the assailant is claiming to have bombs - two inside the cafe and two elsewhere in the financial district.

Police are investigating reports Monis has used hostages' social media accounts to demand a meeting with Australian Prime Minster Tony Abbott.

Some of the hostages have spoken to their families on mobile phones - while five, three male customers and two female staff, have managed to escape.

Journalist Chris Reason, who has a view of the cafe from the Channel 7 building, said the gunman was "extremely agitated" when the hostages fled.

But he told Sky News the cafe had now "gone completely black" - although he could make out a man, thought to be the hostage taker, holding an iPad.

"We can see very little of what is going on inside, which is obviously not good news," said Mr Reason.

"From our position over the last couple of hours we have counted 15 hostages in total. Five of those have escaped.

"They are all ages, all demographics. Fortunately no children that we could see."

Mr Reason said the gunman had been forcing hostages to stand at the window with their hands against the glass - and that they were rotated every two hours.

One woman in that position looked like she had been "crying her heart out", he said.

One of the gunman's reported demands is that an IS flag be brought to the cafe.

Police have confirmed they are working "on a footing" it is a terrorist incident - but they remain "confident" a peaceful resolution can be achieved.

NSW Police deputy commissioner Catherine Burn described it as a "sensitive negotiation" .

Food has now been taken into the cafe for the hostages, none of whom are thought to have been harmed.

Analysing why police had not taken out the gunman, Sky's Foreign Affairs Editor Sam Kiley said: "There are tactical reasons for that.

"If he says there's a bomb inside the building, he may have a dead man’s switch. In other words, if he's shot dead it could go off."

The Australian Prime Minister has convened the National Security Committee for emergency briefings .

"This is obviously a deeply concerning incident but all Australians should be reassured that our law enforcement and security agencies are well trained and equipped and are responding in a thorough and professional manner," said Mr Abbott.

In the hours since the siege began, a social media campaign has been trending globally , with people posting the hashtag #illridewithyou to show solidarity with Muslims.

In a separate development, a 25-year-old man was arrested on alleged terrorism offences in Sydney a few hours before the siege began.

He was seized as part of "continuing investigations into the planning of a terrorist attack on Australian soil and the facilitation of travel of Australian citizens to Syria to engage in armed combat".

The arrest - reportedly as the man left a prayer hall - comes three months after the Australian government raised its terror threat level and conducted large-scale counter-terror raids across the country.

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