Australia's spy agency has been brought in to help combat a rise in the number of so-called laser attacks on aircraft landing at the country's busiest airport in Sydney. Pilots say they are being hit with laser light flashes in what appear to be coordinated efforts to hamper flying. The federal government has called an emergency meeting with officials from Customs, the Australian Security Intelligence Organization and the police. From Sydney, Phil Mercer reports.

Laser lights aimed at incoming planes have forced air traffic controllers in Sydney to divert incoming flights several times.

Officials have said that on one day last month six aircraft were hit by a coordinated stream of blinding green lights. Pilots complained that the lights impaired their vision.

Those responsible used hand-held laser pointers, which are common tools for teachers and others doing presentations, and are freely sold.

Australian police say the laser lights could cause a plane to crash.

Peter Somerville, from the Australian and International Pilots Association, says the problem is getting worse.

"The first thing to note, the most recent attacks is that there has been a level or organization and certainly that is a very unwelcome development and a new stage in this process," said Somerville. "Three or four lasers that were being utilized from, I understand it, different locations and so those things don't happen by accident."

These cluster attacks have worried the authorities so much that Australia's intelligence agency, the Australian Security Intelligence Organization, has been brought in to help find those responsible.

Most major airports across the Australian continent face a similar threat from laser attacks.

Senior officials in Canberra have discussed a range of responses, including restricting the sale of laser pointers and harsher penalties for those using them against aircraft. Culprits already face up to two years in prison and heavy fines.

Catching those responsible has been arduous work for the authorities. They have made only a handful of arrests and the problem has continued.