Mayor Jorge Ramos had announced in mid-November that officers were temporarily relieved of their duties to receive "retraining" and undergo comprehensive background checks amid concern they were colluding with criminals.
While on hiatus, federal agents and soldiers patrolled the city's streets where much of the violence in a drug war has occurred.
Tijuana police pokesman Juan Manrique said the officers returned to their jobs at 8 a.m. Saturday, noting no officers had been fired, the San Diego Union-Tribune reported Sunday.
Military personnel and federal agents will continue their presence in the area to reinforce security, said Gustavo Huerta Martinez, the police department's top deputy.
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