SALT LAKE CITY — Three men are facing federal charges after authorities say they robbed a United States Postal Service mailman at gunpoint in August. 

Court documents said that police received a call about the robbery of a mailman on the afternoon of August 19.

The mailman told police that two strangers walked up to him as he ate lunch in his USPS vehicle in a church parking lot in Salt Lake City. Both had guns, the mailman told police. 

The mailman said the strangers, two men, asked him to hand over his arrow key. USPS uses arrow keys as universal keys to open things like parcel lockers and collection boxes. 

Court documents also alleged that one or both of the men punched the mailman in the face before running off.

The U.S. Postal Inspection Service took over the investigation after police notified it of the robbery.

The documents said the USPIS found nearby surveillance footage that confirmed what looked like an armed robbery. 

Through its investigation, the USPIS said it identified Nathan Suaste, Exodus Matua and Lorenzo Saavedra as suspects in the robbery.

The USPIS alleged that Matua and Saavedra were the two men who robbed the mailman at gunpoint, while Suaste drove the group to and from the robbery.

The three men face charges of robbery of U.S. property.

Kate Davis contributed to the reporting of this story.

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