While the family is not releasing information about the cause of death, those close to the mayor say this was unexpected. And it's a difficult time.
Harvey is in mourning.
They are flying the flag outside City Hall at half-staff.
And purple bunting hangs from the entrance.
Clark was in his second term as mayor of the south suburban town of a little more than 20,000 people. He had about two years left on his current term.
"He was more than a mayor to me. He was a mentor, a visionary leader. It's definitely tough," City Council member Dominique Randle El said.
The town of Harvey has been dealing with a financial crisis. It's in debt by more than $150 million and has been forced to lay off many city workers, including more than half of the fire department employees.
It is a stressful time for the city's elected leaders, who have appealed to the federal and state governments for help.
"Right now, everyone is in shock, as I am, with the passing itself, allowing the family an opportunity to grieve. Governance has to be placed on hold," Cook County Commissioner Dr. Kisha McCaskill said.
The mayor was also a father and grandfather.
He missed the most recent City Council meeting, and friends say he may have been ill at that time, but few suspected anything serious.
Right now, they want to pay tribute and remember their mayor.
"He had a strong vision for the city of Harvey, to move the city forward, work together, put the residents first. And as long as I'm in office, I'm gonna make sure that's the main focus at City Hall," Randle El said.
The city said a special council meeting will be held on Monday at 6 p.m. to appoint a mayor pro temp.
"Our current focus is on allowing the family and the community the time they need to grieve. City operations will continue as normal. Our thoughts and prayers are with the family and the entire Harvey community," current Mayor Pro Temp Shirley Drewenski said.
The acting mayor will be an individual from one of the six alderpeople.
"Mayor Clark was a devoted public servant and a dear personal friend. His integrity, vision and love for the City of Harvey will continue to guide us as we grieve his loss in service to the residents of Harvey, with our hearts foremost with his family," said Keri-Lyn J. Krafthefer, Harvey corporation counsel and city attorney.
The city's statement reads, "The City of Harvey is deeply saddened to confirm the passing of Mayor Christopher J. Clark. We extend our heartfelt condolences to the Mayor's family, loved ones, and all members of the Harvey community during this difficult time.
The City of Harvey is working closely with the Mayor's family and will share additional information when appropriate and with their consent. City services and operations remain in place, and the City continues to serve residents without interruption. A special city council meeting will be called to appoint a Mayor Pro Temp.
At this time, the City respectfully requests privacy for the family as they grieve."
Clark appeared on ABC7 on Oct. 17.
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