Rallies are being held across Russia to protest government plans to raise the eligibility age for retirement pensions by five years.
Thousands attended a Moscow demonstration organized by the Communist Party and other leftist groups. Police, cited by Interfax, put the crowd at 3,000. Organizers said as many as 20,000 had turned out.
Protests were also held on September 22 in many cities across Russia's 11 time zones. Most of them were sanctioned by the authorities.
Unauthorized pension protests earlier this month organized by opposition leader Aleksei Navalny led to the detention of more than 1,000 people across Russia.
The government's plan to lift the retirement age to 65 for men and 60 for women has sparked controversy.
Older Russians worry they won't live long enough to collect benefits. Younger Russians fear keeping people in work for longer could diminish their chances of finding a job.
The proposal has caused a dip in President Vladimir Putin's popularity.
He responded by offering some concessions, but argued that the hike is necessary.
Putin has insisted that raising the retirement age for men and women was essential because Russia’s working-age population was shrinking.
He added that the reforms had been delayed for years and risked causing inflation and increasing poverty.