Navalny tributes removed by group of masked men as Moscow police look on

Floral tributes to Alexei Navalny, President Vladimir Putin's fiercest foe who died Friday in a Russian penal colony, were removed overnight by groups of unknown men while police watched, videos on Russian social media channels show.

More than 100 people were detained in eight cities across Russia after they came to lay flowers in memory of Navalny, according to OVD-Info, a group that monitors political repression in Russia. Russia's prison service said in the Arctic penal colony where he was serving a 19-year sentence. On Saturday, police blocked access to a memorial in the Siberian city of Novosibirsk and detained several people, OVD-Info said.

Videos and photos shared on Russian social media channels showed flowers being cleared from monuments to victims of Soviet-era repressions across Russia. In Moscow, flowers were removed overnight from a memorial near the headquarters of Russia's Federal Security Service by a large group while police looked on, a video showed. But by morning more flowers had appeared.

The news of Navalny's death comes less than a month before an election that will give Putin another six years in power.

It shows “that the sentence in Russia now for opposition is not merely imprisonment, but death,” said Nigel Gould-Davies, a former British ambassador to Belarus and senior fellow for Russia & Eurasia at the International Institute for Strategic Studies in London.

A man lays flowers paying the last respect to Alexei Navalny at the monument, a large boulder from the Solovetsky island

Russia’s Federal Penitentiary Service claimed that Navalny felt sick after a walk Friday and lost consciousness at the penal colony in the town of Kharp, in the Yamalo-Nenets region about 1,900 kilometers (1,200 miles)