The brother of a gunman who killed a police officer and a professor in Russia has appeared on the cover of a documentary film about the killing.

In the documentary, entitled Brothers Karamazin, the brothers of gunman Tamerlan Tsarnaev, take the podium to speak about the murder.

Tamerlan, 26, was killed by police on April 19.

He was wearing a backpack with a suicide vest and a hand grenade.

He was killed in a shootout with police in the southern city of Volgograd.

The documentary features interviews with the brothers, who all spoke with ABC News on the condition of anonymity.

The film shows the brothers’ father, Ruslan, who was in the audience, in tears.

He told ABC News that he believes his brother was killed for being Muslim.

He said he never saw him in the video and said that if he had, he would have been at his son’s funeral.

“He was killed because he was Muslim.

He would have had his own funeral,” Ruslan Tsarnaev said.

Ruslan Tsarnaev told ABC affiliate TV Rain that he and his brother would be going to his brother’s funeral to pay their respects.