A former bank president and two of his customers allegedly conspired to launder drug money in Kansas for Mexican cartels, while two former employees of the small southwest Kansas bank failed to report the suspicious financial transactions, according to charges unsealed Tuesday.

The 37-count indictment is part of a larger national investigation, which has resulted in 20 indictments against defendants in Indiana, Texas, Massachusetts, Georgia, Oklahoma, Colorado and Mexico, the U.S. attorney's office in Wichita said in a news release.

In the Kansas case, investigators seized more than 5,000 pounds of marijuana and more than $2 million in cash.

George Enns, 69, and his wife, Agatha Enns, 67, both of Meade, Kansas, were charged with one count of money laundering conspiracy, 34 counts of money laundering and one count of attempted money laundering. The couple co-owns Southwest Windmill and Waterwell Inc.

Also charged with conspiracy is James Kirk Friend, the 52-year-old former bank president at Plains State Bank. The Plains man also is charged with 29 counts of money laundering and one count of failing to file a suspicious activity report.

A single count each of failing to file a suspicious activity report was also brought against former loan officer Matthew Thomas, 37; and former cashier and IT officer Kathey F. Shellman, 57, both of Plains.

No attorneys were listed for any of the defendants in court records. Friend declined to comment, and the other defendants either didn't return phone messages or no working phone numbers could be found.

The indictment in U.S. District Court in Kansas alleges that between 2011 and 2014, the Enns deposited more than $6.8 million into their account at Plains State Bank; cash deposits totaled more than $1.6 million. The couple also had an account with Bank of America in El Paso, Texas, containing about $1 million.

Prosecutors say the couple crossed the U.S.-Mexico border at least 25 times since 2012, including four occasions in which they were stopped and found to be carrying large amounts of money.

Plains is a rural hamlet of fewer than 1,150 people in southwest Kansas, a region where meatpacking plants have drawn large immigrant populations.

Lindsey Schartz, senior vice president at Plains State Bank, declined to comment Tuesday.

The Associated Press first reported in February the investigation into a Mexican cartel suspected of laundering $2 million in drug proceeds through a small southwest Kansas bank to avoid tighter restrictions on U.S. currency in its home country. The AP obtained an affidavit, inadvertently filed unsealed at the time, outlining the U.S. Drug Enforcement Administration investigation into drug trafficking and money laundering activities between the two countries by the Juarez Cartel/La Linea, sometimes referred to as Mexican Mennonites.

The three former bank employees were issued a summons to appear in court April 29. No record of any summons is listed for the Enns, and the U.S. attorney's office said they are not in custody.