KYIV, Ukraine, June 3, 2025 (AFP) - A Russian rocket attack on the northeastern city of Sumy killed two people on Tuesday, Ukrainian officials said, the latest in a series of escalating attacks on the border region.

The city has come under intense Russian bombardment as Russian President Vladimir Putin has ordered his troops to create a "buffer zone" inside the Sumy region, which borders Russia.

Russia fired five rockets from an MLRS system on the city at around 09:00 a.m. (0600 GMT), the head of the city administration Oleg Grygorov said on social media.

"Unfortunately two people were killed," and 20 more wounded, he said.

"The hits damaged a medical facility, cars and houses," he added.

The regional prosecutor's office posted photos showing burned out cars on a road in the city centre after the attack.

Sumy is around 30 kilometres from the Russian border, and was a vital logistics hub for Ukraine's months-long offensive into Russia's Kursk region.

Attacks on the city have escalated since Russia said in April it had fully recaptured the Kursk region.

More than 30 were killed there in a Russian ballistic missile strike on the city centre in April, one of the deadliest single attacks of the three-year war.

Ukrainian President Volodymyr Zelensky said last week that Russia was amassing some 50,000 troops for an offensive on the region.

A separate Russian drone attack on Kharkiv killed one person, the prosecutor's office said, while the cities of Odesa and Chernigiv were also hit in overnight attacks.