Story highlights Resignation follows weeks of protests over journalist's killing; Jan Kuciak reported on fraud among country's elite

Police are offering a reward of $1.2 million for information on the killer

(CNN) Slovak Prime Minister Robert Fico resigned Thursday after weeks of public protests over the slaying of an investigative journalist who reported on fraud among the country's elite, including people connected to the governing party.

Fico announced his resignation during a ceremony in Bratislava.

Jan Kuciak, 27, and his fiancée, Martina Kušnírová, were found dead in Kuciak's apartment in western Slovakia on February 26 with bullet wounds to the chest and head, respectively, according to the International Press Institute.

Kuciak reported on tax evasion and fraud among Slovak businesses, including people connected to the country's governing party, Smer.

Though the bodies were found February 26 at Kuciak's apartment in Velká Mača, investigators believe the pair were shot sometime between February 22 and February 25, police said.

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