Ukrainian officials detained a man on suspicion of espionage at the site of a Russian missile strike in Lviv.
Police in the western Ukrainian city said they found the man had filmed a rocket flying toward the target and striking it.
They said he also had photos on his mobile phone of military checkpoints in the region that had been sent to two Russian numbers.
The governor of Lviv said five people were injured in several rocket attacks in the city on Saturday.
One strike hit a fuel depot on the outskirts of Lviv and caused a huge fire which the city mayor, Andriy Sadvoyi, said it took emergency responders 14 hours to put out.
The Russian defence ministry said it fired high-precision cruise missiles at military sites in the city including a fuel depot and a plant being used to repair anti-aircraft systems, radar stations and sights for tanks.
The ministry showed video of the missile strikes in Lviv.
Ukraine said it had blocked dozens of Russian spying operations in the invasion so far. The Security Service of Ukraine (SSU) said it had detained more than 350 agents involved in sabotage and reconnaisance missions for Russia.
The SSU said it recently intercepted a group of armed agents in Kyiv who were posing as a Ukrainian military unit.
Operatives have been involved in a wide range of covert activities, the SSU said, including gathering intelligence on the Ukrainian army’s movements in order to inform Russian attacks.
Russia has started destroying Ukrainian fuel and food storage depots, meaning the government will have to disperse the stocks of both in the near future, Ukrainian interior ministry adviser Vadym Denysenko said on Sunday.
A fuel facility near Kyiv was destroyed on Thursday. Russia said it was a key supply for the Ukrainian military.
Russia also said it had fired sea-based long-range missiles at a deployment of S-300 missiles and BUK anti-aircraft missile systems near Kyiv.
The latest attacks came after Russia raised hopes that it was planning to scale back the invasion.
Moscow said on Friday that it considered its military goals largely complete and would turn focus to the “main goal, liberation of Donbas”, the eastern Ukrainian region where fighting between separatists and the government in Kyiv has been going on for eight years.
Volodymyr Zelensky said on Sunday he wanted compromise from Russia over the region.
