(CNN) - A widely-condemned video that shows a Russian riot police officer punching a woman in the stomach on the day of a sanctioned protest for free elections will be investigated by authorities, state-run media in the country has reported.
Footage shows the woman, Daria Sosnovskaya, being detained by two officers at a Moscow rally on Saturday, before one of them punches her and causes her to fall backwards.
She then struggles with officers as she is forced into a police vehicle, the video shows.
The clip has been viewed more than four million times on social media and has caused outrage in Russia. It will now be examined by the country's Investigative Committee -- the main federal investigative body in the country -- Sosnovskaya's lawyer told Russian state news agency TASS after filing a grievance.
In an interview with AFP, Sosnovskaya'slawyer said his client was "supposed to be hospitalized but she refused to, although she received a medical statement confirming that she had gotten a concussion so she can't show up in court now because she feels really bad."
Kremlin spokesperson Dmitry Peskov on Tuesday said a recent series of protests in the Russian capital were "not a crisis," adding that the Kremlin was "monitoring" the situation. "We don't agree with those who call what's happening a political crisis. It's not a crisis. There are protests in many countries, linked to many issues. In European capitals, all around the world," Peskov said in a conference call with reporters. "We need to evaluate things correctly. This cannot be associated with any crisis."
He added: "We are also monitoring those materials that document [acts of] civil disturbance and aggression toward the staff of law-enforcement agencies, that is also unacceptable."
The incident occurred as tens of thousands of people rallied in Moscow for a fifth consecutive weekend, calling for fair local elections. More than 200 people were detained, according to OVD-Info, a group that monitors police. More than 300 had been detained the previous weekend.
Sharing the video to his ten million followers on Instagram, Russian rapper Egor Kreed said: "It doesn't matter what she did, such a thing should not happen!"
"I really hope that they will PAY ATTENTION, they will find him, they will punish him and he will not get away with it," he added, urging his followers to report information about the identity of the officer.
Demonstrators are demanding that authorities allow independent candidates to take part in the city's upcoming local elections. Some protests have been sanctioned by authorities.
Authorities said candidates were barred from running because they had failed to obtain a sufficient number of signatures to be put on the ballot paper. Opposition politicians have rejected this allegation.
Russian President Vladimir Putin has held national office for nearly 20 years. While opposition protests pose no direct threat to his rule, they are seen as one barometer of discontent over his long tenure in office.