Security forces detained more than 3,000 people and violently broke up rallies across Russia as tens of thousands of protesters ignored extreme cold and police warnings to demand the release of Kremlin critic Alexei Navalny.
Prosecutors in St Petersburg said in a statement late Saturday they were probing violations including “on the part of law enforcement” and the use of force against an unidentified woman.
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.