A South Boston man will be sentenced in September after he pleaded guilty to loansharking and gambling charges in federal court in Boston Thursday, part of the same case that led to kidnapping charges against four other suspects, according to the office of US Attorney Andrew E. Lelling.
Tam V. Nguyen, 51, engaged in an illegal gambling business from September 2016 through August 2017, and was a bookmaker who conspired to collect a “large gambling debt” from a bettor, the US Attorney’s office said in a statement Thursday.
“In an intercepted telephone call, Nguyen told a conspirator to ‘go ahead and be firm, be firm with him. That will make him afraid and try hard to take care of it. That’s all,’ ” according to the US Attorney’s office.
Nguyen pleaded guilty to collect extensions of credit by extortionate means and one count of operating an illegal gambling business, the statement said.
Three other suspects in the same investigation — Kim Nguyen, Vinh Quang Huynh, and Quang PT Le, of Dorchester — each were charged with kidnapping, extension of credit by extortionate means, and operating an illegal gambling business.
In November 2016, Le, armed with a knife, was part of a group that kidnapped a victim from outside the victim’s residence, according to a February statement from the US Attorney’s office.
The victim was beaten in an attempt to collect a $40,000 gambling debt, and then the victim was driven back home and told to pay $10,000 the following day.
An additional suspect in the case, Ban “Bo” Tran, was present during the beating and followed the kidnappers in his own car in an attempt to hide the kidnapping, the US Attorney’s office said.
“The next day, the victim went to law enforcement and, under the direction of law enforcement officers, made a series of controlled, recorded payments to Le,” the US Attorney’s office said in the February statement.
Over the next eight months, the victim paid $22,350 to Le, the statement said.
In March, Kim Nguyen was sentenced to a year and a day in prison, plus two years of supervised release, prosecutors said. Le was sentenced in May 2018 to six years in prison and three years of supervised release.
Le and Kim Nguyen each were ordered to pay $6,300 in restitution, prosecutors said.
Huynh pleaded guilty to the charges in December 2017 and is now awaiting sentencing, prosecutors said.
Tran was originally charged with kidnapping, but as part of a plea agreement with the government, pleaded guilty to concealing knowledge of a kidnapping, the US Attorney’s office said in a separate statement in February.
That month, Tran was sentenced to eight months in prison, a year of supervised release, and ordered to pay a $5,000 fine.
John Hilliard can be reached at john.hilliard@globe.com.