Five crosses stood in memory of the five victims killed by a coworker Wednesday afternoon before he turned the gun on himself. Police are still looking for a motive.
"I think this is a time where our whole city is on edge and is hurting, is grieving," said Bishop Paul Erickson, of the Greater Milwaukee Synod of the Evangelical Lutheran Church. "We need to come together."
Democratic U.S. Senator Tammy Baldwin attended the vigil Sunday night.
"Tonight, we stand Milwaukee strong, inspired by the strength we find in each other and by the strength we gain by facing this tragedy of loss together," Baldwin said.
The Molson Coors campus will reopen Monday morning under tighter security, including bag checks and armed officers. The brewery has been part of the fabric of Milwaukee for more than a century.
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"Everybody knows somebody who works there," said resident Kristine Hinrichs. "It's such a fundamental part of our history.
Timothy Nelson usually brings the American flag with him to services honoring fallen first responders in Wisconsin and Illinois. Sunday marked his first time flying the flag as a tribute to victims of a mass shooting.
"I am glad to see the city come together and not forget, but I wish we would come together before something like this happens so maybe something like this doesn't happen," Nelson said.
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Kelly Coleman attended the vigil with her grandson in an effort to teach him to use his voice for change.
"I think it's important for him to be involved and see what's happening in the city at a young age," Coleman said.
She's hoping his future world is more peaceful than the present.
Molson Coors officials said they know it's going to be difficult for employees to return to work.
Counselors will be on campus to provide support, officials said.