"From the first moment all the law enforcement agencies have been involved. The investigators are considering all versions, but the key version is that it was an act of revenge for Pavlo's professional activity," Prosecutor General of Ukraine Yuriy Lutsenko told 112 Ukraine TV channel.
Lutsenko said priority investigation activities are currently under way.
"We are collecting testimonies from those people who live in that area, interviewing witnesses, including those from the notorious Russian channel that always arrive first at the scenes of unexpected murders. We are also interviewing Pavlo's close people," Lutsenko said.
Read alsoChief prosecutor Lutsenko claims gang behind killing of journalist SheremetAs was reported earlier, Pavlo Sheremet, a journalist working for the Ukrainska Pravda online newspaper, was killed in a car blast on July 20. The car being driven by Sheremet belonged to Olena Prytula, his common-law wife and the owner of Ukrainska Pravda.