MOSCOW, February 18. /ITAR-TASS/. Moscow City Court has tightened security ahead of review of the criminal case against Left Front coordinator Sergei Udaltsov and lawmaker's aide Leonid Razvozzhayev accused of planning riots across Russia.

Supporters of the defendants have been gathering near the court. Police have reacted calmly to single pickets so far, supported by a special task force unit which arrived at the scene in several buses.

The hearing, expected to draw a large audience, will be held in the court's largest hall located in the appeals section.

Proceedings over planning mass disturbances were opened against Udaltsov and Leonid Razvozzhayev after viewing of a film entitled Anatomy of Protest showed a meeting between Russian opposition leaders and Georgian politician Givi Targamadze.

Both Udaltsov and Razvozzhayev denied wrongdoing.

Left Front leader Udaltsov has been under house arrest, and Razvozzhayev has been in custody.