A Belarusian activist was found dead in a park near his home in Kyiv early on Tuesday, a day after he was reported missing, Ukrainian police said.
Vitaly Shishov, who led a Kyiv-based organisation that helps Belarusians fleeing persecution, had been reported missing by his partner on Monday after not returning home from a run.
Police said they had launched a criminal case for suspected murder but would investigate all possibilities including murder disguised as suicide.
"Belarusian citizen Vitaly Shishov, who disappeared yesterday in Kyiv, was found today in one of Kyiv's parks, not far from his place of residence," the police statement said.
Ukraine, Poland and Lithuania have become havens for Belarusians during a crackdown by President Alexander Lukashenko following a disputed election last year.
Shishov led the Belarusian House in Ukraine (BDU) group, which helps Belarusians find accommodation, jobs and legal advice, according to its website.
The organisation said on Monday it was not able to contact Shishov. It said Shishov had left his residence at 9 a.m. (0600 GMT) and was supposed to have returned an hour later.
The Belarusian authorities have characterised anti-government protesters as criminals or violent revolutionaries backed by the West, and described the actions of law enforcement agencies as adequate and necessary.
Meanwhile, Belarusian athlete Krystina Timanovskaya who was competing in the Tokyo Olympics was granted a humanitarian visa from Poland after refusing her team's order to fly home early.
The sprinter, 24, said she had “forced” to leave the event for the airport after criticising coaches. She sought help from Tokyo police in the airport.
Her husband and daughter have escaped Belarus to the Ukraine and have been declared as safe.