Tens of thousands turned out in rainy weather in Moscow to participate in a "March for Peace" against Russian actions in Crimea.
The march began at Pushkin Square and went to Sakharov Prospekt where people, many holding Russian and Ukrainian flags, gathered to listen to speakers, including opposition leaders.
Speaking to the crowd, Russian opposition leader Boris Nemtsov explained the purpose of the gathering.
"This is an antiwar march and an antiwar rally," he said. "This is a rally against [Russian President Vladimir] Putin's madness. This is a rally for our good neighborly relations with our brothers in Ukraine. I believe that what [Putin] is doing is a disaster for Russia and a disaster for all citizens of our country."
A parliament deputy from the opposition A Just Russia party, Dmitry Gudkov, mocked the planned referendum in Crimea.
"Everything is clear about the referendum," he said. "It will proceed, and under the barrels of guns they will show that 146 percent, or even 200 percent of Crimean residents will vote. The turnout has already been taken care of."
The Moscow rally ended peacefully as did another rally against Russian military actions in Crimea in St. Petersburg.
Similar rallies were held in other Russian cities.
Another rally supporting the Russian government's stance against "fascism" in south and eastern Ukraine was held in Moscow on March 15.
That rally attracted some 15,000 people who, led by an orchestra, took part in the "March of Brotherhood and Civil Opposition" from Trubnaya Square to Revolution Square.
In Donetsk, Ukraine, where one person was killed and several injured during rival protests on the night of March 13, a pro-Russian group was holding a rally on the square outside the local security service headquarters.
A number of people have attempted to storm the building but police fended them off.
Some of the protesters have climbed drainpipes and reportedly removed the Ukrainian flag from the building and replaced it with a Russian flag.
More than 30 people were reported to have been detained in Kharkiv as of the morning of March 15 after violence overnight left two people dead.
Local police said they had seized a small number of weapons and some 20 bottles filled with flammable liquids.