The hacker movement known as "Anonymous Mexico" has posted a statement condemning "the bad government" on the press section of Mexico's Defense Department website.
The statement signed by group appeared on the press link for the site as late as early Thursday.
The statement includes a video showing street protests on Dec. 1, when police cracked down on anti-government demonstrators.
The Defense Department issued a statement late Wednesday when the hacking began, saying its website was "temporarily out of service."
The department said no internal computer networks or information had been affected.