A former Russian MP who fled to Ukraine last year and was known to be a critic of President Vladimir Putin was shot and killed outside an upscale hotel in Kiev on Thursday, the Associated Press reported.

Denis Voronenkov, 45, who was once a Putin supporter, took on Ukrainian citizenship after he arrived in the country in October 2016.

Details of the circumstances surrounding the killing are still unclear, but another former Russian MP, Ilya Ponomarev — the only MP to vote against the annexation of Crimea — said on Facebook that Voronenkov had been on his way to meet him.