The man accused of detonating an explosive device at a metro station in the Belarusian capita of Minsk pleaded guilty in court on Thursday.
A bomb went off in Minsk's most crowded metro station on April 11, killing 15 people and injuring over 300.
"I plead guilty to the metro blast," Konovalov said when asked by the judge in a Minsk court.
He also pleaded guilty to the July 3, 2008 Independence Day concert blast in Minsk, which left at least 55 people injured.
However, Konovalov denied involvement in a blast in at a discotheque in the city of Vitebsk in 2005, which left 50 people injured.