Ukrainian media reports say police are searching the residence of the mayor of the northeastern city of Kharkiv.
Prosecutor-General Yuriy Lutsenko was quoted as saying that a hotel in Kharkiv, where Hennadiy Kernes is currently residing, was being searched on September 15.
Lutsenko also said a house in the city belonging to the mother of opposition lawmaker Mykhaylo Dobkin was also being searched.
According to Lutsenko, the searches are part of an investigation into the alleged involvement of Kharkiv city officials into an illegal land privatization.
Kernes barely survived a shooting attack in April 2014, a time of growing instability in eastern Ukraine and a month after Moscow forcibly annexed the Crimean Peninsula from Ukraine.
Kernes initially gave his backing to the pro-Russia separatists in the east before later switching his loyalty to the Ukrainian government.
Kharkiv, Ukraine's second-largest city, is just 20 kilometers from the Russian border.