The warning, which came in a ministry statement, followed last week's clashes in downtown Cairo when thousands of riot police beat and chased demonstrators who gathered to show solidarity with the two judges, who blew the whistle on electoral fraud in last year's parliamentary vote. A total of 255 also were arrested.
Hearings in the case of the two judges are scheduled to resume Thursday.
Meanwhile, the country's oldest human rights organization - the Egyptian organization for Human Rights, or EOHR - described the latest police assaults as a "setback to reform."
Last week's assault on demonstrators also drew worldwide criticism.
The European Union called the police operation "disproportionate" and questioned arrests made under the provisions of emergency laws that allow arrests without warrant and the detention of suspects for months without charge.
The EU said it hoped Egypt would not again extend the emergency laws beyond 2008, noting that President Hosni Mubarak had promised to repeal the measures and ensure they were used only to combat terrorism, not target political opponents.
The U.S. State Department urged the Egyptian government to permit peaceful demonstrations "on behalf of reform and civil liberties."
The FSB of Russia has distributed the footage of video surveillance over suspects, who allegedly worked to orchestrate a military coup in Belarus and planned to assassinate its president, Alexander Lukashenko