Sometime overnight on Friday, someone broke into the Mr. Sub on Richmond Street by smashing the drive-thru window.
Chatham-Kent police say the thieves took the safe and fled.
The safe contained between $6,000 and $11,000 in cash and property, police say.
Anyone with information is asked to contact Const. Kai Kraft at kaik@chatham-kent.ca or 519-436-6600. Anonymous callers may call Crime Stoppers at 1-800-222-TIPS (8477) and may be eligible for a cash reward.