Pavel Sheremet, a Belarussian known for his outspoken criticism of his home country’s leadership and his friendship with the slain Russian opposition leader Boris Nemtsov, was driving to work in the car of the website’s owner when it was blown up.

The killing was a throwback to the days of violence against journalists that Ukraine, under a pro-Western leadership since the 2014 Maidan protests, hoped to have shed.

“I don’t rule out that the cynical murder of Ukrayinska Pravda journalist Pavel Sheremet could be used to destabilize the internal political situation in Ukraine,” said Anton Gerashchenko, a lawmaker and advisor to the Interior Ministry.

“The investigation will examine all possible theories for the murder, firstly linked to his journalistic activities. Even a Russian connection should not be excluded.”

CONCERN IN THE KREMLIN

In Moscow, Kremlin spokesman Dmitry Peskov, said: “The murder of a Russian citizen and journalist in Ukraine is a very serious cause for concern in the Kremlin.”

Sheremet, who was given Russian citizenship after fleeing political persecution in Belarus, had told Reuters in October that he did not feel comfortable visiting Moscow any more.

“I’m threatened often and given hints. Every time I go to Moscow, it’s like I’m in a minefield,” he said in an interview.

He said Ukraine needed strong, independent media to counter the influence of outlets controlled by business tycoons.

“Now the problem of freedom of speech and objective journalism is becoming again a serious issue,” he said.

“As far as internal politics is concerned, I can see oligarchic games again, black PR, the use of media to settle scores and solve political problems.”

Tributes poured in from colleagues and Ukraine’s president and prime minister. Sevgil Musayeva-Borovyk, the editor-in-chief of Ukrayinska Pravda, which has made its name exposing corruption, called him “very brave”.

It was not clear whether the bomb had been set off by remote control or a timer.

NEMTSOV’S FUNERAL

Sheremet’s friend Nemtsov, a vocal critic of the Kremlin, had been working on a report examining the Russian military’s role in the Ukraine crisis when he was shot dead in central Moscow last year. Sheremet led the tributes at his memorial service.

“The last time we met was at the funeral of Boris Nemtsov, and of course I couldn’t have known that a similar thing would happen to Pavel,” Anatoly Lebedko, leader of the Belarussian opposition party United Civil Party, told Reuters.

In 2002, Sheremet won a journalism prize from the Organization for Security and Co‑operation in Europe (OSCE) for his reporting on human rights violations in Belarus, including the disappearances of opposition politicians and journalists.

The OSCE called on Wednesday for action to address the safety of journalists in Ukraine.

The founder of Ukrayinska Pravda, Georgiy Gongadze, was an investigative journalist who was murdered 16 years ago, his decapitated body discovered in a forest outside Kiev.

The incident helped to precipitate the Orange Revolution of 2004/05, which resulted in an election re-run and the victory of an opposition presidential candidate.

(Reporting by Natalia Zinets, Sergei Karazy, Alessandra Prentice and Margaryta Chornokondratenko in KIEV, Jack Stubbs and Maria Tsvetkova in MOSCOW and Andrei Makhovsky in MINSK; Writing by Matthias Williams; Editing by Kevin L)