The Security Service of Ukraine (SBU) detained two Kyiv residents on suspicion that they assisted Russian forces in their missile attack against the capital on Sept. 21, the SBU announced on Sept. 27.

According to the report, the two suspected collaborators provided the Russian military intelligence (GRU) with coordinates to target critical infrastructure in the city, namely energy facilities, shortly before the attack.

The two suspects allegedly came to the attention of Russian intelligence because of their anti-Ukrainian posts on social networks, which they started publishing after the start of the full-scale invasion.

Subsequently, the GRU reached out to them online and recruited them to collect intelligence in Kyiv, asking them to provide photographs and geolocations of critical energy infrastructure sites, the SBU said.

They were also allegedly tasked with monitoring military bases and the movement of Ukraine's Armed Forces around the capital.

The two suspects reportedly received a monetary reward for their collaboration. They face life in prison.

Russia launched a mass wave of missile attacks against multiple oblasts on Sept. 21, killing two people and injuring at least 26.

According to Ukraine's state energy operator Ukrenergo, this marked the first mass attack by Russian forces against the Ukrainian energy infrastructure in six months.

Energy facilities in western and central Ukraine were damaged, and there were blackouts in Rivne, Zhytomyr, Kyiv, Dnipropetrovsk, and Kharkiv oblasts.

Russian forces escalated their attacks against Ukraine's energy grid during the previous fall and winter, hoping to cripple the country's power grid and undermine resistance against the invasion. Kyiv warned that Moscow is likely to return to this strategy during the next winter months.