Several thousand opposition supporters have gathered in central Moscow for an unauthorised rally and at least one prominent opposition figure has been detained.

In a new sign of a widening crackdown on Russian opposition, a criminal investigation has begun into leftist leader Sergei Udaltsov and several other opposition activists for allegedly plotting mass riots.

Russia’s opposition will test Vladimir Putin’s grip on power today in nationwide protests that promise to be the largest demonstration of public outrage since the dying days of the Soviet Union.

TENS of thousands took to the streets across the globe for May Day yesterday, to press for workers’ rights amid tough economic times and to back an array of other causes.