Arturas Zuokas, mayor of the Lithuanian capital Vilnius, was admitted to an intensive care unit in the city Tuesday, reported the Baltic News Service.
According to his wife, the 43-year-old politician was apparently poisoned, though whether this was accidental or not is not yet clear, dpa reported.
In a bizarre coincidence, another youthful mayor of a Baltic capital is also in intensive care. Riga's 34-year-old mayor Nil Usakov was admitted to hospital on Sunday after collapsing while competing in the Riga half marathon.
A spokesman for Usakov said the mayor would soon be transferred to a specialist unit in Berlin due to the seriousness of his condition.