KYIV, Ukraine -- A car bomb killed at least one person Friday night in Russian-occupied southern Ukraine, according to Ukrainian and Russian officials, highlighting the war's reach far beyond the front lines as Ukrainian partisans aim to undermine their occupiers.
The blast occurred in Mykhailivka, a town in Ukraine's Zaporizhzhia region. The vehicle targeted was carrying "four supporters of the Kremlin," Ivan Fedorov, the Ukrainian mayor in exile of the Russian-occupied city of Melitopol, about 30 miles south, said on the Telegram messaging app.
Vladimir Rogov, a Russian occupation official in the Zaporizhzhia region, confirmed the attack in a Telegram post, saying the bomb killed a "local businessman" named Sergei Didovoduk and injured two others. On Saturday, he said authorities opened an investigation.
The attack comes as Ukrainian forces are preparing for a highly anticipated counteroffensive that analysts believe will take place in southern Ukraine. Ukraine's troops will probably aim to sever the land routes that connect Russia to Crimea, which Moscow illegally annexed in 2014, according to analysts and Western officials.
"We are ready," said Ukrainian President Volodymyr Zelenskyy in a recent interview with The Wall Street Journal that was published Saturday.
Much is riding on the coming counteroffensive, especially on the heels of Russia's recent capture of the eastern Ukrainian city of Bakhmut. In the meantime, partisan attacks like the one Friday night have become a staple in occupied areas as Ukrainian insurgents target the Russian military and so-called Russian collaborators.
Rogov portrayed Didovoduk as a member of local civil society who "regularly fed neighbors in need in his cafe for free." According to Rogov and unverified footage of the aftermath of the attack posted on social media, Didovoduk died in a Soviet-made Niva car, an unassuming sport utility vehicle.
Ukrainian officials suggested Didovoduk's cafe, the Hetman, was frequented by Russian soldiers and occupation officials.
The cafe is named after the customary title of the head of the Cossack state that existed in Ukraine in the 17th and 18th centuries and played a major role in the foundation of modern Ukraine.
Didovoduk was registered to compete for Russia's governing party in upcoming local elections, Rogov said. The Kremlin has pushed forward with plans to stage local elections in September in four Ukrainian regions that Russia illegally annexed last year, an attempt to legitimize the moves despite the constantly changing frontiers of the territory under Russian control.
Ukraine has denounced the elections in the annexed regions -- Zaporizhzhia, Kherson, Luhansk and Donetsk -- as a sham.
The killing of Didovoduk also raises questions about the legality of partisan attacks under the internationally recognized law of war, including whether partisans are considered combatants.
Ukrainian partisans say they are civilians and the legal basis for their activity is regulated under Ukrainian law, not the laws of war that include prohibitions on a soldier targeting a civilian official. But under international laws, civilians become combatants when they start taking part in hostilities.
In other developments, a nationwide inspection of bomb shelters across Ukraine found that of the "over 4,800" shelters it had inspected, 252 were locked and a further 893 "unfit for use," the interior minister posted Saturday.
Zelenskyy ordered inspections in response to accusations and questions raised by the deaths of three people who had been locked outside their neighborhood shelter Thursday at a children's health clinic in Kyiv.
Amid an ongoing criminal investigation, the Kyiv regional prosecutor's office reported that four people were detained in a criminal probe into the 33-year-old's death on Thursday outside the locked shelter. The prosecutor's office said that one person, a security guard who had failed to unlock the doors, remained under arrest, while three others, including a local official, had been put under house arrest.
According to the prosecutor's office, the suspects face up to eight years in prison for official negligence that led to a person's death.
Also Saturday, Kyiv Mayor Vitali Klitschko said city authorities have received "more than a thousand" complaints regarding locked, dilapidated or insufficient air-raid shelters within a day of launching an online feedback service.
In a Telegram update, Klitschko reported that "almost half" of the complaints concerned facilities being locked, while about a quarter had to do with them being in poor condition. Some 250 Kyiv residents wrote in to complain of a lack of nearby shelters.
The interior ministry said over 5,300 volunteers, including emergency workers, police officers and local officials, would continue to inspect shelters across Ukraine.
Russia launched a pre-dawn missile barrage Thursday at the Ukrainian capital, killing a 9-year old, her mother, and another woman, in what was the highest toll from a single attack on Kyiv over the past month. A 33-year-old woman died as she and others waited to enter a locked shelter, which left the group at the mercy of falling missile fragments, her husband told Ukrainian media.
Attacks in the Russian border region of Belgorod, where some areas have become a new front line, continued Saturday. Gov. Vyacheslav Gladkov said the area of Shebekino, a town of about 40,000 people 6 miles from the border, had been coming under Ukrainian shelling since the morning.
Two people were killed, he said, bringing to seven the number of people killed in recent days.
Late Saturday, the governor of the Dnipropetrovsk region, Serhiy Lysak, said 13 people were injured in shelling in the region; one person was pulled from a damaged residential building in the town of Podgorodnenska and other were believed to be trapped in the rubble.
Elsewhere, Ukrainian regional officials reported Saturday morning that Russian shelling had killed at least four civilians across the country in the previous 24 hours.
A 67-year-old man died early Saturday as Russian forces shelled the northeastern Kharkiv region, Gov. Oleh Syniehubov said on Telegram. According to Syniehubov, two other civilians were killed Friday and overnight, while six more, including a 3-year-old boy, suffered wounds.
In the frontline Kherson region in the south, two boys aged 10 and 13 were hospitalized with "serious" injuries after an explosive device detonated Saturday in a village playground, regional Gov. Oleksandr Prokudin reported. Prokudin also said that five others, including two children, were wounded by Russian shelling over the previous day.
In the Sumy province further west, a Russian mortar shell killed an 85-year-old man as he sat by the orchard outside his house, the Ukrainian prosecutor general's office reported Saturday.
It was not immediately possible to verify the above claims by regional authorities in Ukraine and Russia.
Information for this article was contributed by Thomas Gibbons-Neff and Anatoly Kurmanaev of The New York Times and Susie Blann of The Associated Press.