A US Navy missile successfully struck a defunct American spy satellite and probably destroyed a tank carrying 450 kilograms of toxic fuel in an exercise opposed by Russia [Images] and China since it involved the use of Pentagon's missile defence system.

The school bus-sized satellite passing at 210 kilometres over the Pacific was hit at 10:30 pm EST Wednesday (0900 hrs IST on Thursday) by a Standard Missile-3, which is designed to intercept incoming enemy missiles and not orbiting satellites.

Meanwhile, China has asked the US to provide details about the exercise so that 'relevant countries can take precautions'.

"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 in Beijing [Images] when asked for a reaction to the shoot down.

The Bush administration said targeting the satellite was necessary as it carried a fuel tank whose content, hydrazine, posed a potential health hazard to humans if it landed intact. A network of land, air, sea and spaced-based sensors confirmed the interception of the non-functioning National Reconnaissance Office satellite, the Pentagon said.  

"Nearly all of the debris will burn up on re-entry within 24-48 hours and the remaining debris should re-enter within 40 days," it added in a statement.

Officials were hopeful that the tank containing the toxic fuel was destroyed.

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

The exercise received so much international attention with the potential for widespread political ramification that the decision to pull the final trigger to launch the missile was given by Defence Secretary Robert Gates rather than a military commander.
Russia had earlier accused the US of wanting to test a space weapon under the pretext of shooting down the damaged satellite.

"The impression arises that the United States is trying to use the accident with its satellite to test its national anti-missile defence system as a means of destroying satellites," Russia's defence ministry said over the weekend.

The interception was carried out by the USS Lake Erie warship, which fired a single modified tactical Standard Missile-3, hitting the satellite as it travelled in space at more than 17,000 mph. USS Decatur and USS Russell were also part of the task force.

The Bush administration has organised hazardous materials teams under the code name 'Burnt Frost' to be flown to the site of any dangerous debris that might land on the ground in the US or elsewhere.

Image: The USS Lake Erie launching the Standard Missile-3 at the non-functioning National Reconnaissance Office satellite.
Reportage : PTI | Photograph: US Navy via Getty Images