Police in Colleyville led the investigation with help from the Texas Department of Public Safety, the U.S. Secret Service and U.S. Postal Inspectors, prosecutors said.
The probe started after FedEx in Grand Prairie alerted detectives about suspicious shipments of cash, according to search warrants reviewed by NBC 5.
The suspects are charged with engaging in organized crime and theft.
One of them, Olusegun Odunwole, 33, was employed for five years as a prison guard by the Texas Department of Criminal Justice. He resigned after he was charged last year, the agency said.
More charges are possible, assistant Tarrant County district attorney Lori Varnell said.
Odunwole’s attorney, Samuel R. Terry, did not respond to a request for comment.
An attorney for another defendant, Saheed-Olukayode Akinyemi, 31, said prosecutors haven’t proven anything yet.
“Certainly my client is presumed to be innocent as it stands right now and we look forward to seeing what evidence the state believes it has and addressing them in court,” said attorney, Benson Varghese.
Dominick Marsala, an attorney for Ifeanyichukwu-Festus Obi, 40, emailed a short statement.
“While targeting elderly people for any nefarious purpose is obviously egregious, under the laws of our country, my client has the presumption of innocence,” he said.
Wes Ball, an attorney for Obianuju Orakposim, 40, said his client may be a victim of the scheme.
“She may have been a victim of these scam artists and got sucked into this thing,” Ball said. “It remains to be seen how this shakes out. She has the presumption of innocence.”