Sydney Siege: The Moments Hostages Fled Gunman's Clutches (PICTURES AND VIDEO)

These extraordinary images and video show the moments five people managed to flee the gunman holding hostages in central Sydney.

Three men and two women have emerged from the cafe in two separate escapes, literally running into the arms of police who have surrounded the cafe where the man is holding an unknown number of people.

The most dramatic video shows a woman wearing a Lindt apron run from the shop, crying with fear, and get grabbed by a waiting officer.

She and another woman wearing an apron ran out of the cafe within moments of each other. The other women held her hands up when she saw the police and then hold her hand to her heart at the shock of it.

A photographer captured the expression of the first woman at the exact moment she was grabbed by the police, an image that has become the most eye-catching of the whole event.

A police officer grabs one of the hostages after she flees the cafe at around 6am UK time, 5pm local time

What is exactly happening in the cafe is unclear.

Around an hour before the two women fled, three men fled together - two from the front entrance and one from an emergency exit.

It was initially claimed they were released by the gunman but it was later reported they had escaped.

They ran around a corner and were taken in by police.

One of the men raises his arms at the sight of gun-carrying police

Another of the men with police just after his escape

It remains unclear how many hostages remain in the cafe, as police are refusing to confirm numbers.

Here are the major developments:

• Five people have fled from a Sydney cafe where a gunman took an unknown number of hostages at the height of Monday morning rush hour.

• Two people inside the cafe were earlier seen holding up a flag containing an Islamic declaration of faith, but there is only believed to be one lone hostage taker

• It has since been reported that the hostage-taker has demanded an Islamic State flag to be delivered to the cafe, and to speak with Australian prime minister Tony Abbott

• Demands have been made directly through at least three media organisations in Australia

• The first development came six hours after the hostage crisis began, when three men were seen running from a fire exit of the Lindt Chocolat Cafe in downtown Sydney.

• Shortly afterward, two women, one after another, sprinted from the cafe and into the arms of heavily armed police. Both were wearing aprons with the Lindt chocolate logo, indicating they were cafe employees.

• The hostages are not believed to have been harmed. Only one escapee was taken to hospital, who said he was in a "satisfactory" condition.

• The public has been told to stay away from Martin Place, home to the state premier's office, the Reserve Bank of Australia, and the headquarters of two of the nation's largest banks. The state parliament house is a few blocks away.