Violence by Russian police under scanner after arrest of 3,300 protesters

The violent response by police in Russia has come under review as reports of arrest of more than 3,300 protesters have emerged. 

Prosecutors in St Petersburg said in a statement late Saturday that they were probing violations during demonstrations held in support of jailed Kremlin critic Alexei Navalny -- including "on the part of law enforcement" and the use of force against an unidentified woman.

Police clashed with demonstrators in Moscow as tens of thousands took to the streets across the country on Saturday following Navalny's call to protest against President Vladimir Putin's rule.

Putin's fiercest critic was detained at a Moscow airport on arrival a week ago from Germany, where he had been recovering from a near-fatal poisoning with a nerve agent.

OVD Info, which monitors opposition rallies, said on Sunday that police seized at least 3,324 demonstrators across dozens of cities, with 1,320 people detained in Moscow and 490 in the second city Saint Petersburg.

It was the largest number of detentions at opposition rallies in the history of modern Russia. 

A number of protesters were also injured at the rallies in the capital and Saint Petersburg.

The statement was released after local media published a video showing a middle-aged woman falling to the ground after being kicked by riot police.

In the video, a woman -- identified as Margarita Yudina -- is seen asking three policemen in full riot gear why they were detaining a young unarmed protester. One of the policeman than kicks her in the stomach.

A representative of Saint Petersburg's Dzhanelidze hospital said that Yudina was hospitalised Saturday night with a head injury.

Saturday's protests took on an unprecedented geographic scale, spanning more than 100 cities across the country.