Nearly a dozen NASA websites run from the heart of Silicon Valley were hacked on Tuesday and remain offline days later, following a politically motivated digital broadside against the space agency.

“My understanding is the entire NASA Ames Center had a hack attack that took the website down,” spokesman JD Harrington told FoxNews.com. However, another NASA spokesman later denied that the entire center was taken down, instead saying that the attack was of a much smaller scope.

The Ames Center in Mountain View, Calif., where scientists once worked on the Viking and Pioneer spacecraft, currently houses high-tech facilities for NASA and others; Google leases 42.2 acres at Ames for a planned 1.2 million square foot of office and R&D space, for example.

'The entire NASA Ames Center had a hack attack that took the website down.'

— NASA spokesman

A group calling itself BMPoC took credit for the hack, saying it had taken down the sites to protest U.S. cyberintelligence activities.

“On Sept. 10, 2013, a Brazilian hacker group posted a political message on a number of NASA websites." a NASA spokesman told FoxNews.com. "Within hours of the initial posting, information technology staff at the Ames Research Center discovered the message and immediately started an investigation, which is ongoing.  At no point were any of the agency’s primary websites, missions or classified systems compromised.”

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The group has apparently hacked not just one but several websites that housed information on the Kepler space telescope, planetary exploration, the moon and more, all run out of Ames Research Center.

They include kepler.arc.nasa.gov, event.arc.nasa.gov, academy.arc.nasa.gov, planetaryprotection.nasa.gov, nextgenlunar.arc.nasa.gov, lunarscience.nasa.gov, iln.arc.nasa.gov and more, according to NASA Watch.

A notice on the kepler.arc.nasa.gov website simply reads “Down for Maintenance: The requested webpage is down for maintenance. Please try again later.”

But a member of the science team also confirmed that the site was down due to an attack.

“The Kepler website was hacked yesterday, so we are working to get it back up,” Steve Howell, a researcher on the Kepler science team, told FoxNews.com on Thursday.

The same hacker defaced four websites in April, according to news reports at the time.