Australia: 'Very disturbing' hostage siege in Sydney

(USAToday) - At least one armed person held an undisclosed number of hostages in a cafe in downtown Sydney on Monday, and Australian Prime Minister Tony Abbott said the events may be "politically motivated.''

A flag with Arabic script was displayed through the cafe window.

The standoff gripped downtown Sydney, shutting down government offices, public transit and schools as it dragged through the day.

The normally busy and crowded business district of the city was on virtual lockdown, with hundreds of officers on the scene.

New South Wales Police Commissioner Andrew Scipione said at an afternoon news conference that "an undisclosed number of hostages'' were being held by "an armed offender.'' Some media reports said 13 people were being held hostage, but there were conflicting reports of larger numbers.

"We have not yet confirmed this is a terrorism-related event,'' Scipione said.

Television and still images from the scene showed several people inside the cafe holding their hands up in the air, pressed against windows, with a visible black flag bearing what appeared to be Arabic script.

"It's a flag that we've had people looking at. We're still trying to work out what it stands for,'' the police commissioner said.

He said that police had not established direct communication with the hostage taker.

"We do not know the motivation of the perpetrator,'' Abbott said in a televised address. He called it "very disturbing.''