A New York City Fire Department emergency medical technician was arrested and Grant Prestoncharged with stealing $600 from an undercover investigator posing as a sick patient.

The investigator went undercover after receiving allegations of theft involving the EMT, according to the NYC Department of Investigation.

Luis Carrillo Jr., 43, was charged with felony grand larceny in the fourth degree and misdemeanor petit larceny and official misconduct. Upon conviction, the felony is punishable with up to four years in prison and the misdemeanors are punishable with a year in prison.

Carrillo was arraigned in Queens Criminal Court Wednesday night and released on his own recognizance.

He is scheduled to appear in court again on Oct. 6.

"This defendant took an oath to provide emergency medical assistance with diligence and compassion, but instead used his position to steal from an individual who appeared to be in need of care, according to the charges. The disgraceful charged conduct stands in stark contrast to the FDNY’s countless EMTs who act with honor and integrity every day, delivering critical care to New Yorkers in need," Jocelyn Strauber, the commissioner of NYC's Department of Investigation, said in a statement.

The undercover test was conducted around 3:30 a.m. on Wednesday when an investigator posed as a sick patient in need of medical attention. Under DOI surveillance, the undercover investigator was then transferred in an ambulance to Elmhurst Hospital in Queens.

The undercover investigator saw the EMT remove his wallet while in the ambulance, which contained $1,100 in marked bills. Once the investigator was dropped off at the hospital, he discovered that $690 was missing from his wallet, according to the DOI.

DOI stopped the ambulance after it left the hospital and was able to recover $600 in marked bills from the EMT's right pocket and arrested him. Investigators did not find the other missing $90.

Carrillo, who was suspended upon his arraignment, has been an EMT since October 2012.

The DOI thanked Fire Commissioner Laura Kavanagh for the department's "assistance" with the sting operation.