However, it appeared that Russian deputy defence minister Alexander Formin was the only foreign official there.
Myanmar's security forces have cracked down on new protests as the leaders of its coup marked Armed Forces Day.
In several locations, security forces sought to disperse them forcefully, as has become standard practice, Reports on social media, not immediately verified, said several demonstrators were shot dead Saturday morning.
"All the released are the ones arrested due to the protests, as well as night arrests or those who were out to buy something", a member of a legal advisory group told Reuters. "The fact that so many children are being killed on an nearly daily basis shows a complete disregard for human life by security forces".
Thirteen people were killed in various incidents in Mandalay, Myanmar Now said.
More than 320 people have been shot dead in the suppression of protests since the coup on 1 February.
Security forces opened fire at protestors gathered outside a police station in Yangon's Data suburb, where four of them were killed and ten wounded. Reuters could not independently verify the reports.
It called for the release of all those detained since the coup and for the military to "withdraw from active engagement in politics".
But although many foreign governments have condemned the military's actions, Thomas Andrews, special United Nations rapporteur on human rights in Myanmar, said the diplomatic response was slow and called for an emergency summit on the crisis.
"Women, youth and children have been among those killed", she said in a statement.
"We need to join together", he said.
Half an hour later, troops took the wreath away, witnesses said.
"The military generals are celebrating Armed Forces Day after they just killed more than 300 innocent civilians", he said, giving a rough estimate of the toll since protests first erupted weeks ago.
"Russia is a true friend", Min Aung Hlaing added.
Moscow's support for the junta is important as it is a permanent member of the United Nations Security Council and along with China, which has also refrained from criticism, can block potential UN actions.
Myanmar's economic growth is set to shrink by 10 percent this financial year as military rule hammers one of the region's fastest-growing economies, according to the World Bank.
Myanmar "has been heavily affected by protests, worker strikes, and military actions", it said.
In Washington, the US Treasury Department announced new sanctions targeting Myanma Economic Holdings Public Company Limited (ed. correct) and Myanmar Economic Corporation Limited.
"This war has not ended until we win", one protester, Phone Naing, told Reuters.
"But they will likely get much worse without an immediate, robust, worldwide response".
Senior General Min Aung Hlaing on Saturday spoke at a ceremony in Naypyitaw on Armed Forces Day, which commemorates the start of resistance against the Imperial Japanese military in 1945.
"The strongest storm comes after the silence", protest leader Ei Thinzar Maung said in a social media post.
"The day for the people to revolt against the Tatmadaw (military), which has been oppressing people for ages.has come again".
Police fired at a street demonstration in the city of Mawlamyine and arrested 20 people, the Hinthar Media Corp said.
A Molotov cocktail (firebomb) was hurled at Aung San Suu Kyi's party headquarters.
It has tried to justify the takeover by saying a November 8 election won by Ms Suu Kyi's National League for Democracy (NLD) was fraudulent - an accusation the electoral commission has rejected.