They were first tipped off something was suspicious in August.
Since then Florida Lottery officials have been keeping a watchful eye on lottery sales at the Akel Market and Kwik Stop Food Store in Pompano Beach.
Wednesday, Florida Lottery officials and deputies with the Broward Sheriff's Office took action, walking into both stores to remove lottery machines.
They have temporarily suspended their contract to sell lottery tickets, a move that could be permanent depending on the outcome of their investigation.
Tom Dolan, the Miami district manager for the Florida Lottery, told Local 10 all tickets issued by both stores are valid.
Lottery spokesman David Bishop said he could not offer specifics on the kind of fraudulent activity it is believed store owners were engaged in leading to Tuesday's crackdown. He said, in general terms, fraudulent activity could include things like someone with a winning ticket trying to redeem it at the store, being told by a clerk it is not valid and then that clerk redeeming it for his or her self.
"It's something serious enough for us to move on it," he said.
No arrests have been made and no criminal charges have been filed. Lottery officials said that is pending the outcome of the ongoing investigation.