The canine, whose name means great in Latin, served as part of an explosives detection team along with his partner, Officer Benjamin Zink.
Magnus served for 10 dedicated years and died due to sudden medical complications.
"Together the pair helped to protect and secure the NJ TRANSIT system and all within the great state of New Jersey," NJ Transit police said.
"The entire NJTPD would like to thank K9 Magnus for his faithful years of service to the department and the community."
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