Members of a Russian nationalist group have disrupted the screening in Moscow of a film about the ongoing conflict in eastern Ukraine.
The movie Bullet's Flight by director Beata Bubenets was due to be screened at the documentary film festival Artdocfest in the Oktyabr movie theater on December 10.
But reports said several individuals sprayed an acrid liquid in the hall, prompting an evacuation.
The leader of the South East Radical Block (SERB) movement, Igor Beketov, told the Interfax news agency that he was among three members of the group detained by police over the incident.
Law enforcement authorities have not commented.
Fighting between Ukrainian government forces and Russia-backed separatists has killed more than 10,000 people in eastern Ukraine since April 2014.