Russian forces released the kidnapped mayor of the northern Ukrainian city of Slavutych on Saturday, just hours after the military had seized a local hospital and subsequently held the city's highest-ranking politician hostage, the New York Post reported.

Yuri Fomichev's kidnapping prompted thousands of protesters to line the streets of Slavutych — located roughly 100 miles north of Kyiv and near the Belarus border — and demand the mayor's release.

The Russian forces then acquiesced to the protesters' peaceful plea, and reportedly retreated to the outskirts of town, without incident.

In a post from the messaging app Telegram, Oleksandr Pavlyuk, the head of the Kyiv Regional Military Administration, first alerted the world to Fomichev's kidnapping and eventual release.

"The Russians opened fire into the air," Pavlyuk wrote of the Russian troops' brief surge into Slavutych, the Post reported. "They threw flash-bang grenades into the crowd. But the residents did not disperse, on the contrary, more of them showed up."

The 31-day war between Russia and Ukraine has affected many corners of the Ukraine territories. But until the temporary seizure of the local hospital, Slavutych had not seen much conflict. The city was originally constructed in 1986, as a means of sheltering nuclear power plant workers after the infamous Chernobyl nuclear disaster.

Relieved by his release, and emboldened by the Slavutych protesters, many of whom waived Ukrainian flags around town, Fomichev told the crowd of his bargaining with Russian troops.

"In captivity, I negotiated with the occupiers," Fomichev told the large audience, in a video confirmed by The New York Times. "It was agreed that if it is confirmed that our military is not in the city, everything will be calm."

Fomichev then reportedly added, "Slavutych remains under the Ukrainian flag!"

Russian President Vladimir Putin initiated a full-scale invasion of Ukraine on Feb 24. Russian troops immediately began targeting, shelling and destroying key infrastructure facilities within various Ukraine markets, launching missile and air strikes on cities and villages.

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