CHICAGO (AP) — A trial in a massive, long-running counterfeit-documentation scheme centered in Chicago but that included a murder in Mexico City ended Tuesday with jurors finding three defendants should face mandatory life sentences.

The operation was based in Chicago's Little Village neighborhood and flourished for at least 15 years until authorities broke it up in 2007. It generated about $3 million in annual sales of fake Social Security cards, driver's licenses and other documents.

In a last stage of the six-week trial in U.S. District Court in Chicago, jurors determined Tuesday that Julio Leija-Sanchez, 37; his brother Manuel Leija-Sanchez, 45; and Gerardo Salazar-Rodriguez, 40, should get mandatory life for racketeering conspiracy because it involved murder.

The jury returned with guilty verdicts on multiple counts Monday.

It was Salazar-Rodriguez who carried out the murder of an up-and-coming rival in Mexico City in 2007, firing more than a dozen shots into a taxi cab, prosecutors said.

Authorities dismantled the operation and arrested dozens of suspects in 2007. At trial, prosecutors relied on hours of wiretapped conversations, including where Salazar-Rodriguez allegedly can be heard bragging to the Leija-Sanchez brothers about the murder.

At times, the counterfeiters sold 100 sets of fraudulent IDs each day for about $200 per set, which typically included a phony Social Security card, and either an immigration green card or a driver's license. Aspects of the operation also were conducted in Mexico, prosecutors said.

Sentencing was set for Sept. 12.