NASA reported an act of sabotage aiming for the launch of the ISS this fall, as a computer was deliberately damaged by a space program worker, who knew that it was heading for the station via the shuttle Endeavour.

The worker was not employed directly by the space agency, but for a NASA subcontractor and he cut wires inside the computer and damaged a similar computer that was not meant to fly to space. Fortunately, the sabotage was discovered before the equipment was loaded onto the spaceship, NASA said Thursday.

Bill Gerstenmaier, NASA's space operations chief, said the damage, which occurred outside the launch site in Florida, was reported to the space agency by the subcontractor. "It was disclosed to us as soon as the event occurred, about a week and a half ago."

Even if the subcontractor had missed the problem on inspections, NASA officials would have found the problem before launch, he said: "The damage is very obvious, easy to detect. It's not a mystery to us."

He also declared that the same subcontractor builds gauges for the shuttle's wings and other station computer components and that all of them have been found in good order, no signs of further tampering having been found so far.

Gerstenmaier did not want to identify neither the saboteur nor the name of the subcontractor and its location, as he cited an investigation by NASA's inspector general. He also declined to speculate on the causes of the sabotage, whether it was meant as an act of terrorism, or a workplace dispute that generated a need for revenge.

He did stress out that the incident had nothing to do with a continuing strike at NASA's Kennedy Space Center by a machinists union. NASA hopes to fix the computer and launch it Aug. 7 as planned aboard Endeavour, but it is not a critical component of the ISS or the shuttle, so it is expendable.

"If we don't get it repaired in time, we'll fly without it," said NASA spokesman Kyle Herring. "It's not an issue."