This is evidenced by the data of the official resource on notification.

Also, an air alert operates on the territory of Poltava, Cherkasy, Kirovograd, Dnepropetrovsk, Kharkov and a number of other regions. 

On December 21, it was reported that an air alert had been declared throughout Ukraine. 

Also, the Ukrainian edition "STRANA.ua" reported that after the explosion in Kyiv, a column of smoke rose.