A network of radars and satellites designed for the US missile defense system confirmed that the interception occurred at approximately 10.26 pm eastern standard time (0326 GMT Thursday).

US Defence Secretary Robert Gates was informed in a conference call with senior military officials 'that the mission was a success, that the missile had intercepted the decaying satellite', Pentagon press secretary Geoff Morrell said.

'The secretary was obviously very pleased to learn that, and he congratulated General (James) Cartwright and General (Kevin) Chilton as well as their teams on a job well done,' he said.

Mr Gates had given the generals the go-ahead for the shoot down several hours earlier as he flew from Washington to Honolulu, a base for the three Aegis warships involved in the intercept attempt.

Mr Morrell said Mr Cartwright, the vice-chairman of the Joint Chiefs of Staff, and Gen Chilton, the head of the US Strategic Command, told Mr Gates 'the conditions were ripe for an attempt'.

Seas were initially believed to be too rough but they calmed down later in the day as a six hour window opened for the attempt.

The USS Lake Erie, a guided missile cruiser, fired a single modified tactical SM-3 missile, 'hitting the satellite approximately 247 kilometres over the Pacific Ocean as it traveled in space at more than 7,000 miles (44,000 kilometres) per hour', the Pentagon said.

The objective was to hit a tank on the schoolbus-sized satellite containing 1,000 pounds of hydrazine, a fuel that the Pentagon said could pose a hazard to humans if the tank survived re-entry and landed in a populated area.

'Confirmation that the fuel tank has been fragmented should be available within 24 hours,' the Pentagon statement said.

Satellite debris will re-enter the Earth's atmosphere immediately because of the relatively low altitude at which the satellite was intercepted, and most will burn up on re-entry within two days, the Pentagon said.

But it could take up to 40 days for all the debris to re-enter, it said.

China calls on US to provide data on satellite shootdown
In Beijing, China called on the United States on Thursday to provide information about its shooting down of the defunct US spy satellite and voiced caution about the potential international impact of the operation.

'China is continuing to closely follow the possible harm caused by the US action to outer space security and relevant countries,' foreign ministry spokesman Liu Jianchao said when asked for a reaction to the shootdown.

'China further requests that the US fulfil its international obligations in earnest and promptly provide to the international community the necessary information and relevant data so that the relevant countries can take precautions.'

Russia's defence ministry said on Sunday that it looked like a veiled weapons test and an 'attempt to move the arms race into space'.

US officials have insisted that the aim was to prevent potential risk to humans on Earth from the de-orbiting satellite, and not to test an anti-satellite weapon or keep its secrets from falling into the wrong hands.

Admiral Timothy Keating, the head of the US Pacific command, acknowledged similarities with the Chinese shoot down but said this one was significantly different because the United States gave public notice first.

'They just shot, they didn't tell anybody about it. Not even all of them knew about it,' he said of the Chinese.

Admiral Keating said he has been in contact with his counterparts in the region about the operation.

Their response has been, 'Thanks for the call, good luck, keep us posted,' he said.

The Lake Erie was carrying two missiles in case the first attempt failed.

The USS Decatur, an Aegis destroyer, was armed with a third missile, while the Aegis destroyer USS Russell tracked the event from pierside in Pearl Harbor.

The warships are equipped with powerful radars capable of tracking a medium range missile warhead in space, and are armed with SM-3 interceptor missiles.

Software changes were made to the missile used in the shoot down so that it could recognise a satellite as its target rather than a ballistic missile. -- AFP