RIA reported that law enforcement officers in the region of Bashkortostan had detained the boy who was being investigated under laws related to “terrorism and treason” which carry a prison sentence of up to 20 years.

RIA said the boy, whom it did not name, was accused of gathering information and painting graffiti for Ukrainian intelligence in return for money since the autumn of 2024.

It said he had confessed to his crime under questioning.

It quoted him as saying that he went to Ryazan to gather information on the refinery at the Ukrainians’ behest in early January.

The Ryazan refinery, which is located around 240km south of Moscow, suspended operations after an attack by Ukrainian drones on Monday, three industry sources told Reuters.

Ukraine has repeatedly targeted Russian energy infrastructure to try to undermine Moscow’s financing for the war.

The strikes have knocked out around 10% of Russia’s total refining capacity, Reuters reported earlier this month.