Harris County Precinct 3 Assistant Chief Clint Greenwood was killed April 3.
On April 15, a crawfish cookoff drew thousands of people who donated thousands of dollars, which was to be given to Greenwood's family and the 100 Club.
However, two organizers of the fundraiser alerted investigators there was alleged suspicious activity surrounding another one of the organizers.
Chambers County Sheriff Brian Hawthorne said the eyewitnesses said $10,000, or even more, is unaccounted for.
"Obviously it's very disturbing if in fact the allegations are true," said Hawthorne.
Jason Schofield and Frank Bejarano brought the case to the attention of detectives. They said they helped with the fundraiser and were counting the money after the event with the other person who is now being investigated.
Schofield and Bejarano said at one point that man said he had about $10,000 in debts from the fundraiser to pay, and that he then forced Schofield and Bejarano to leave the trailer where they were counting the money.
"There was still a lot there to count. We have no idea how much was in there," said Schofield.
They just don't want someone taking advantage of the Greenwood family, after all they have been through.
"It boils my blood. It boils my blood for somebody to do that," said Bejarano.
The man at the center of the investigation insists he did nothing wrong.
ABC13 is not identifying the man as he has not been arrested or charged with any crime. He calls the situation a "nightmare" and said the evidence will support his innocence.
"There was nothing that can be proven," he told ABC13, "... and they have all the receipts. That's it."
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