The blast shook an apartment block in Energodar, wounding the official and two of his guards.
The mayor of the Russian-held city of Energodar in southeast Ukraine and two of his security guards were injured in an explosion on Sunday, local law enforcement said.
The mother of the mayor Andrey Shevchik reportedly resides in the entranceway of an apartment block. A police representative told Russia's TASS news agency that an improvised explosive device was planted inside an electrical distribution box.
The mayor had received numerous threats from the Ukrainian side, he said.
Shevchik and the two guards are being treated in the hospital with injuries of varying severity.
According to local media, no residents of the apartment block were affected by the explosion.
Images on social media show the destruction caused by the blast, with a metal door torn off and thrown into the courtyard. The remains of the explosive device can also be seen, along with metal bolts used as lethal fragmentation components.
The largest nuclear power plant in Europe is in Energodar. In the early days of the military operation in Ukraine, the city of some 50,000 fell under Russian control, as Shevchik, a Ukrainian national, appointed by Moscow to head the local administration. Ukraine s government does not recognise Shevchik as a mayor, viewing him as an illegal occupation force.