The Russian drone attack on the train station in Shostka, Sumy region, Ukrainian President Volodymyr Zelensky announced on Telegram on October 4.
He also posted a video recording the scene of passenger train cars being destroyed, on fire and many other train cars having broken windows.
Dozens of railway passengers and staff were injured in the attack, according to President Zelensky.
Sumy Oleh Hryhorov region governor said the train hit by the bullet was traveling from Shostka to the capital Kiev. Medical and rescue staff were working at the scene.
About 30 people were injured in the attack. No deaths were reported.
Russia has stepped up airstrikes on Ukraine's rail infrastructure, attacking almost every day for the past two months.
In other developments related to the conflict in Ukraine, a Ukrainian energy company said that Russian drones and missiles attacked the Ukrainian power grid from the night of October 3 to the morning of October 4, the day after the largest attack on Ukrainian gas facilities since the conflict broke out.
According to operator Chernihivoblenergo, the attack damaged energy facilities near Chernihiv, a northern city near Russia's border, leading to power outages, expected to affect about 50,000 households.
Chernihiv Dmytro Bryzhynskyi, head of the military regime, confirmed that Russia's night-time attack on the city had caused many fires.
The day before, Russia launched its largest attack since the conflict began targeting gas facilities operated by Ukrainian Naftogaz Group.
According to the Ukrainian air force, Russia launched 381 drones and 35 missiles into Ukraine on October 3.
The Ukrainian military added that from the night of October 3 to October 4, Russian forces launched 109 more drones and 3 ballistic missiles into Ukraine. 73 drones were shot down or diverted.
