** Shares of China's Xiaomi 1810.HK drop 6.1% to HK$46.20, their lowest since February 18, and on course for fourth consecutive session of decline

** Stock set for the biggest one-day pct fall since March 25; top pct loser on Hang Seng Tech Index .HSTECH, which gains 0.6%

** Xiaomi said on Tuesday that it was actively cooperating with police after a fatal accident involving a SU7 electric vehicle on March 29 and it had handed over driving and system data

** Hang Seng Commerce & Industry Index .HSNC gains 0.5%, Hang Seng Index .HSI adds 0.4%

** Stock up 37% YTD

(Reporting by Donny Kwok)

((donny.kwok@thomsonreuters.com))