Russian Prime Minister Vladimir Putin has officially announced his victory in the presidential elections following his third run for top office.

Immediately after the polls closed, Putin declared his victory in front of some 100-thousand supporters gathered at Manege Square, located next to the Kremlin. President Dmitry Medvedev was also beside him.

Local exit polls show Putin collected close to 60 percent of votes.

Meanwhile, some opposition candidates and election watchers have released several thousand cases of alleged election fraud on social networking service sites.

However, Russia's Central Election Commission and the International Election Observation Mission say there have been no serious election violations.