Two days of protests across Russia against reopening a factory on Lake Baikal culminated Sunday when hundreds marched in Moscow.
The environmental group Greenpeace put the number of protesters at 1,000.
Police did not interfere in Sunday's march, which came after hundreds protested in other cities Saturday against Prime Minister Vladimir Putin's order to reopen the Baikal Pulp and Paper Mill.
Environmentalists say the plant dumps sewage and wastewater into Lake Baikal - the world's oldest and largest freshwater lake.
Authorities closed the plant in 2008, putting 1,500 people out of work.
But Mr. Putin has ordered it reopened.
He says his order does not mean that there is no pollution in and around the lake. But he said the situation needs to be examined more closely without emotions or politics.
Some information for this report provided by AFP.