MOSCOW — Russian police wrestled with demonstrators and arrested hundreds of people in central Moscow on Saturday at a protest demanding that opposition candidates be allowed to run for the Moscow city council.

The dispute comes as the Kremlin is struggling with how to deal with strongly opposing views in its sprawling capital of 12.6 million people.

OVD-Info, an organization that monitors political arrests, said 317 people had been detained an hour after the protest started, while the city police department said the number was 295, according to state news agency Tass.

Lines of helmeted riot police tried to push back the protesters in Moscow, some of whom resisted physically. Demonstrators shouted slogans including "Russia will be free!"

The crowd appeared to number several thousand people, but there was no official estimate of its size.

There was no immediate information on what charges the detainees might face.

Police block a street during an unsanctioned rally in the center of Moscow, Russia, on July 27, 2019. Alexander Zemlianichenko / AP

Alexei Navalny, Russia's most prominent opposition figure, had called Saturday's protest and was sentenced Wednesday to 30 days in jail for doing so.

Before the protest, several opposition members and aspiring candidates were detained throughout the city, including Ilya Yashin, Dmitry Gudkov and top Navalny associate Ivan Zhdanov.

Police presence was heavy at the mayor's office on Tverskaya Street, one of Moscow's main thoroughfares, with police trucks and buses parked in the building's courtyard and other buses positioned nearby to take detainees away.

Protesters attempt to break through a police cordon during an unauthorized rally demanding independent and opposition candidates be allowed to run for office in local election in September, in Moscow on July 27, 2019. Maxim Zmeyev / AFP - Getty Images

The decision by electoral authorities to bar some opposition candidates for having allegedly insufficient signatures on their nominating petitions already sparked several days of demonstrations even before Saturday.

The Moscow city council, which has 45 seats, is responsible for a very large municipal budget and is now controlled by the pro-Kremlin United Russia party. All of its seats, which have a five-year-term, are up for election on Sept. 8.