"There were drug transactions going on right in front of the school," she said.
The police said he was also carrying $1,100, believed to be proceeds from drug transactions.
Investigators said one of the men, apparently angered over a drug transaction, shot the other.
"I thought a drug transaction had happened right in front of my eyes."
A police spokesman said he had "no doubt" that the money was part of a drug transaction.
During the course of the drug transaction, Hatcher got separated from the surveillance team.
"It turned out that probably what was going on was some kind of drug transaction," he said.
Their mission is to disrupt drug transactions along the route.
He wondered if perhaps the trio might have been involved in some kind of big drug transaction.
A news release said official vehicles of the county sheriffs were used in the drug transactions.