Russia's Federal Security Service (FSB) said on Monday that it had detained a 24-year-old Russian woman in Crimea who was attempting to sabotage rail infrastructure bringing military equipment to the frontline in Ukraine, Russian state news agency TASS reported.
The woman had corresponded with a Ukrainian handler regarding the planned attack, and was under suspicion of terrorism and treason, the FSB was cited as saying in the report.
The FSB has said it has detained a string of Ukrainian agents in recent days, amid an upsurge in Ukrainian strikes on Russia amid presidential elections that concluded on Sunday.