Beams from four green lasers, which appeared to come from an area just southwest of the city, were directed at planes for 15 minutes late on Saturday, in what officials labeled a 'coordinated attack.' They do not know who was behind it.

Mr David Campbell, the police minister of New South Wales, said the state was now considering a ban of the small laser pointers, usually used in classrooms or presentations.

'There are some penalties that police can impose now, but we're looking to make these items a prohibited weapon in certain circumstances which would lead to substantial fines and possible jail terms,' he said.

Other Australian states have already initiated the laser ban. In the United States, it is a federal offense to point a laser at an aircraft.

Civil Aviation Safety Authority spokesman Peter Gibson said it was unlikely the lasers could lead to a crash, especially on commercial flights with two pilots. But some pilots said they were temporarily blinded or got headaches from the glare. -- AP