Chile's National Archive on Friday presented more than 1,000 restored secret documents pertaining to the operations of "Department 50," a police unit that was instrumental in dismantling Nazi spy cells operating in Latin America during the Second World War.

The Investigations Police of Chile (PDI) declassified those documents in mid-2017, and on Friday a final tranche of thirteen restored and digitalized volumes was unveiled to the public.

Those volumes contain images and information revealing how Department 50 investigated and tracked down paramilitary Nazi groups between 1937 and 1947.

"We received a large quantity of documents from the PDI on the activities of Department 50, an intelligence unit tasked with verifying suspicions about the infiltration of Nazi cells in the center and south of the country," National Archive Director Emma De Ramon told EFE.

The archives show that those paramilitary cells entered Chile with the assistance of the German embassy and spread out to different regions of the country.

Their aim was to recruit young people of German origin to spy on the movements of Chilean and Latin American troops.

"This network was dismantled by Department 50, and these documents pertain to that investigation, which was conducted on a judge's orders and sanctioned by existing law," De Ramon said.

The National Archive began working on an initial tranche of 11 volumes it received from the PDI, but it needed the economic support of the Foundation for the Preservation of the Memory of Chilean Judaism to restore the final tranche of documents, which it said was in worse condition.

The volumes include reports, telegrams, notices, identity cards, photographs, passports and other material that were restored using sophisticated techniques and later digitized and made available to the public on the National Archive's Web site.

The PDI's Department 50 was created in 1941 following the discovery that Nazi groups had settled in the southern part of Chile earlier that decade.

These groups, which also established a presence in Argentina, intended to control traffic through the Strait of Magellan, a strategic sea route between mainland South America and Tierra del Fuego that connects the Atlantic and Pacific Oceans.

In 1942, the unit dismantled a German radio station that operated in the central Chilean city of Quilpue and sent encrypted messages to Germany about Allied merchant vessel itineraries.

A year later, 20 people were arrested in Santiago and the southern part of the country in an operation in which investigators discovered hi-tech radio equipment, cash, a codebook for sending messages to Germany and plans to bomb mines in northern Chile.