RIO RANCHO, N.M. - Navajo Code Talker David Patterson Sr. passed away Sunday at the age of 94.

Patterson passed away in Rio Rancho, New Mexico, from pneumonia and complications from subdural hematoma on Sunday, according to a release from the Navajo Nation.

Patterson served in the Marine Corps from 1943 to 1945, when he was honorably discharged. He received the Silver Congressional Medal of Honor.

His son, Pat Patterson, said his father didn’t talk much about his service, but he was proud of being a Navajo Code Talker.

According to the U.S. Marine Corps, Code Talkers took part in every assault by Marines in the Pacific during WWII from 1942 to 1945 serving in all Marine six divisions.

The Code Talkers were a vital part to the Allied forces victory, as the Navajo language is the only spoken code to have never been deciphered.

Patterson is survived by his children, David Patterson Jr., Marcus Patterson, Sandy Johnson, Michael Patterson, Pat Patterson and Calvert Lee.

"It’s a sad day on the Navajo Nation when we lose a national treasure like we did in losing Navajo Nation Code Talker David Patterson, Sr.,” Navajo Nation President Begaye said. “Beyond his service in protecting our freedom, he was a beloved husband, father and grandfather. The Office of the President and Vice President extends our condolences to his family during this time of mourning.”

Funeral services will take place at Christ The King Catholic Church in Shiprock, New Mexico, with date yet to be determined. Desert View Funeral Home is handling funeral arrangements. Patterson will be buried on the Military side of the Shiprock Cemetery.