Ukrainian President Petro Poroshenko has dismissed Security Service (SBU) first deputy chief Yuriy Artiukhov, deputy chiefs Vitaliy Tsyhanok and Viktor Yahun, and head of the SBU investigative department Vasyl Vovk.

The decrees on dismissing the said officials were published on the presidential website on Friday evening.

Hosting a conference attended by top-ranking law enforcement and security officials earlier in the day, Poroshenko gave acting SBU chief Vasyl Hrytsak time until Friday evening to submit formal proposals on dismissing a number of senior SBU officials.

"Petro Poroshenko noted that he expected the acting SBU chief to submit formal recommendations on dismissing SBU First Deputy Chairman Yuriy Artiukhov, SBU Deputy Chairmen Vitaliy Tsyhanok and Viktor Yahun, and SBU investigative directorate chief Vasyl Vovk until the end of the day," the presidential press service reported on Friday.

Hrytsak was also supposed to make proposals on "the SBU's considerable personnel reinforcement to ensure reform."