Russian police officers stand in front of St. Basil's cathedral as part of heightened security measures in central Moscow December 11, 2011. [Photo/Agencies]

MOSCOW - Russian President Dmitry Medvedev on Sunday wrote in his Facebook page that he has ordered probes into the alleged elections fraud, though he disagreed with protesters' slogans and statements in Saturday's rallies.

Tens of thousands of Russians staged a peaceful massive protest in several Russian cities on Saturday against alleged fraud in last Sunday's parliamentary elections, in which the ruling United Russia garnered an absolute majority in the new State Duma, or the lower house of parliament.

"Under the Constitution, Russian citizens have the freedom of speech and the freedom of assembly. People have a right to express their positions and that is what they did yesterday. It is good that everything was held within the law," Medvedev wrote.

"I agree neither with the slogans, nor the statements made in the protests. Nevertheless, I have ordered probes into all reports from polling stations regarding the compliance with the electoral laws," he added.

However, the president didn't reveal more details about his instruction.

Russia's Central Elections Commission (CEC) announced Friday that the United Russia party gained 238 out of 450 seats in the new State Duma.