A man from the occupied Donetsk region was found guilty of providing information to the Russian military and sentenced to 12 years in prison, the Ukrainian Security Service (SBU) said in a Telegram post.
An investigation found the man had sent voice messages to Russian forces in the area with information about the location of Ukrainian military units, equipment, weapons storehouses, military bases and headquarters.
SBU officials detained the man at his apartment in the Eastern Ukrainian city of Sloviansk and seized his phone.
They said the information he provided had been used to direct Russian missiles to target the city.
Russian forces aimed to capture Sloviansk in summer 2022, before getting bogged down fighting for Bakhmut, 45 kilometers (27 miles) away.
Sloviansk has regularly been shelled by Russia. Eleven people, including a toddler, were killed in April when a missile struck an apartment block in the city.
The SBU said the man had communicated through two Russian military “liaisons,” a member of a motorized rifle regiment and a battalion commander of a motorized rifle brigade, in order to anonymize his reports.
The SBU Telegram post did not name the man but published photographs of his arrest, including laid on the ground with his hands behind his back and his face censored.