MINSK, October 26. /TASS/. Demonstrators formed solidarity chains in several parts of the Belarusian capital on Monday morning in support of the "people's ultimatum" put forward by the opposition.

Medics from the cardiologic research center Kardiologiya, many carrying red-and-white flags and emblems, lined up on Grushevka street. A similar demonstration is underway on Mayakovsky Street near the Mikhalovo metro station.

Witnesses have reported arrests on Pervomayskaya Street. In some parts of the city protesters blocked roads. Highway patrols were promptly dispatched there to restore traffic.

A group of 100 students at the Belarusian State University are holding a sit-in protest in the university's main building. More students have joined them.

Former presidential candidate Svetlana Tikhanovskaya's ultimatum to President Alexander Lukashenko expired on Sunday. The opposition has called for strikes at industrial enterprises starting from Monday.