An NYPD detective died Monday while serving his third tour of duty with the U.S. Air National Guard.

Detective Joseph Lemm was a 15 year veteran of the NYPD who served the city in the Bronx Warrant Squad. Over the course of the past decade, Lemm was deployed three times, serving active duty once in Iraq and twice in Afghanistan.

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He died Monday serving that second tour in Afghanistan.

"Detective Joseph Lemm epitomized the selflessness we can only strive for," said Commissioner Bill Bratton in a statement, "putting his country and city first." Bratton added the entire NYPD grieved the loss of Lemm, whom he called "a selfless public servant who dedicated his life to protecting others."

The NYPD said that Lemm leaves behind a wife and two children.