Here's from an updated boom! entry from Abdymok:
parliament deputy hryihory omelchenko, who chairs the ad hoc rada committee investigating the murder of georgy gongadze and other crimes, on july 1, 2004 urged that kravchenko be detained by law-enforcement authorities for his own protection.
"the measure could save his life. i know kravchenko's psychological state now. his life is in danger: he could have a breakdown and commit suicide, or could be murdered, or they could murder him and make it look like a suicide, or he could simply vanish," omelchenko said.
Abdymok also has Kravchenko's bio in English. From what I know, Kravchenko was a tennis fan, seen a couple times at private celebrations of members of Ukraine's tennis "beau monde." But that's not too relevant.