A weekend glitch in Japan's air traffic control system, which disrupted 1,600 flights and affected 270,000 passengers, was seen Sunday to have dealt another blow to the credibility of the country's high-tech industry.

The failure, the largest computer outage in Japan's aviation history, also prompted local media on Sunday to question the country's security preparedness at a time when it is gripped with a North Korean nuclear arms threat.

Newspaper editorials read: "Can we prevent cyber terrorism this way?" or "A possible threat to the country's security?".

A flight data processing system, which covers the largest of Japan's four air control zones and automatically transmits data including flight numbers, went down for four hours Saturday, transport ministry officials said.

Due to a reprogramming hiccup, the main system and its backup went down immediately after being switched on, grounding all domestic flights for half an hour and forcing air controllers to operate the system manually.

The glitch is the latest in a run of troubles that have dogged information systems and other state-of-the-art equipment built by Japan's big technology firms.

"The credibility of their technol-

ogies are again put into question," the leading business daily Nihon Keizai Shimbun commented Sunday.

In April last year, Mizuho, the world's largest financial group by assets, suffered a string of embarrassing computer failures after restructuring its three group banks into two new banks.

Automatic teller machines failed and millions of money transfers were delayed or duplicated, triggering harsh criticism from the government.

The troubled air traffic control system was built by Japan's NEC Corp., which was at the centre of controversy last year over a range of mobile phones that consumers

complained overheated.

Fujitsu Ltd. was also hit last September when defects were found in some of its computer hard disc drive devices.

The high-tech firms needed to examine whether recent costcutting steps, including the outsourcing of production to other Asian nations, were to blame for the blunders, the Nihon Keizai said.

On Sunday, six domestic flights were cancelled at Tokyo's Haneda airport as airlines could not fully procure aircraft and other equipment for juggled schedules.