Operation Gridlock was organised by the Michigan Conservative Coalition after Democrat Governor Gretchen Whitmer extended a stay home order until April 30 and shut down schools and businesses deemed non-essential.
Roads were packed with cars on Wednesday as drivers honked their horns in protest outside the capitol building in Lansing.
Other protesters held signs which read "Gov Whitmer We Are Not Prisoners" and "Michigander Against Gretchens Abuses".
According to Darren Green from the Michigan State Police, traffic was backed up for more than a mile around the capitol in several directions.
“This arbitrary blanket spread of shutting down businesses, about putting all of these workers out of business, is just a disaster. It’s an economic disaster for Michigan,” coalition member Meshawn Maddock said. “And people are sick and tired of it.”
The coalition group posted Operation Gridlock as an event on Facebook in which they referred to the lockdown measures as "tyranny".
The post reads: "Our Governor and her allies are infecting all of us with their radical, progressive agenda.
"There is no reasoned and public plan to promote our overall physical and economic health."
Gov Whitmer acknowledged the pain but said the restrictions were necessary to stop the spread of the Covid-19 that has killed more than 1,900 Michigan residents and overwhelmed hospitals in the Detroit area.
Gov Whitmer said she was “really disappointed” to see protesters close together without masks.
“I saw someone handing out candy to little kids barehanded,” the governor told reporters.
“People are flying the Confederate flag, and untold numbers who gassed up on the way here or grabbed a bite on the way home. We know that this rally endangered people.
“This kind of activity will put more people at risk and, sadly, it could prolong the amount of time we have to be in this posture.”
During the rally, Republican House Speaker Lee Chatfield, who has urged Gov Whitmer to amend her orders, waved an American flag from a window at his office.
The number of deaths in the US is nearing 30,000.
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