The Ukrainian security service, or SBU, has identified two people who helped Russian target an Iskander missile on the village of Hroza, in the Kharkiv region, that killed at least 53 civilians.

In a statement, the SBU and the office of the Ukrainian prosecutor general said Dmytro Mamon, 23, and his brother Volodymyr, 30, started working with Russia when the village was occupied early in the war.

Both had worked in law enforcement in Hroza and joined the Russian puppet ‘department of internal affairs’ of the Kharkiv region.

Before Hroza was retaken by Russian forces, the brothers and their families managed to flee to Russia, where they started to recruit informants in Ukraine.

"Under the guise of friendly conversations and correspondence in the messenger with fellow villagers, the traitors asked people for information about the deployment of defence forces and mass events in the region," the SBU said in a statement.

The locals allegedly "did not understand that the brothers were actually conducting subversion against Ukraine," the prosecutor general’s office said.

In a conversation with his wife, Dmytro Mamon admitted to his brother’s involvement in the missile strike on Hroza and asked her not to tell anyone about it.

Russia fired an Iskander missile on the village on 5 October, hitting a cafe where people attended a wake for a Ukrainian soldier. At least 53 civilian people were killed and another six wounded.

Dmytro and Volodymyr Mamon were charged of treason, with one of them additionally charged with aiding and abetting the violation of the laws and customs of war, combined with premeditated murder.