"I'm very thankful to the MI audience for joining me in supporting this cause", said Mars.
"God bless you MI!"
The Mars' donation is being made by the singer himself and tour promoter Live Nation through funds from his MI concert.
Flint's water problems began in 2014 when the city transitioned from Detroit's water system to the Flint River.
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Bruno Mars' "24K Magic World Tour" kicked off its North American leg in Las Vegas following a three-month European excursion. The water was improperly treated, leading to elevated levels of lead.
During his performance of his song "Just the Way You Are", Mars paused to make the surprise announcement, dedicating the donation to "our brothers and sisters in Flint".
Bruno Mars did a seven-figure solid for the city of Flint, Mich., during his show on Saturday night (Aug. 12) in suburban Detroit.
The pop artist is not the first to call attention to the ongoing water crisis, he is preceded by Michigan-native rap artists, Eminem and Big Sean, Flint-born filmmaker Michael Moore as well as Wiz Khalifa, Beyonce, Cher, and comedian Jimmy Fallon among a host of others.