MOSCOW, March 19 - RAPSI. A court postponed a case of Left Front leader Sergei Udaltsov for an indefinite time. The opposition activist was detained on Sunday for participating in the unauthorized protest rally at the Ostankino television and radio tower.

RIA Novosti has yet to obtain comments from the Interior Ministry.

The ministry's press office reported on Monday morning that the police released over 100 people detained at the television tower. The detainees have been held liable for administrative offences and will now face the trial.

The opposition held a protest rally against the "Anatomy of Protest" documentary showed by the NTV channel last week which sparked a public outcry and was widely condemned in the Internet.

The film alleged, among other things, that some people, particularly those attending the White Ring action on February 26, are paid for their attendance.

Udaltsov was sentenced to a ten-day administrative arrest several days ago for disobeying police. The law enforcement agencies accused him for the attempt to organize an unauthorized procession after the rally on March 10. However, the Moscow Presnensky Court later changed the arrest with a 1,000-ruble fine for him.