NEW YORK » A former U.S. soldier known as Rambo has been sentenced to 20 years in prison for conspiring in a plot to kill a Drug Enforcement Administration agent.

Joseph Hunter was sentenced today by U.S. District Judge Laura Taylor Swain in Manhattan. The 51-year-old, 20-year Army veteran cried as he apologized for his crimes.

Showing some leniency, the judge credited Hunter for an honorable military career that led to numerous commendations. But she said his “grave and serious” crimes warranted stern punishment.

Hunter was brought to the United States in 2013 to face conspiracy charges. Prosecutors say he led two other ex-soldiers — an American and a German — in an $800,000 plot to kill the agent in Liberia.

Hunter pleaded guilty after his arrest in the sting operation.