False news stories can form part of the threat against Danish soldiers on duty in the Baltic country from next year, the minister said.
Soldiers will therefore receive training in how to manage threats of this kind once the Nato mission starts, reports broadcaster DR.
“This is a completely new world. Denmark's soldiers should be extremely aware of that. I have therefore arranged with the military that soldiers being sent on duty in January be oriented and trained in how to protect themselves,” Frederiksen told DR.
“It is easy to imagine that they could be subjected to intimidation and false rumours,” the minister added.
Soldiers already in the region have had experiences that suggest the precaution against false rumours is a necessary one, DR writes.
In February, a story claiming that a German soldier had raped a local girl spread on social media in Lithuania.
The story had already spread quickly by the time Lithuanian authorities were able to confirm that it was false.
Both Nato and the EU have now established special units to fight against misinformation.
Frederiksen said the campaign of false news – of which the Lithuanian story is one of a number of examples – was an attempt to “sow distrust amongst us”.
“Other nations that are already there have been subjected to false news, slander and harassment. So obviously this is a completely different set up than we are used to, for example from Afghanistan,” Flemming Vinther of the Army Constable and Corporal Society (Hærens Konstabel- og Korporalforening), which has several members scheduled to travel to Estonia.
“It is certainly my impression… that the military leadership is taking this very seriously and is well-prepared to manage the situations that may arise there,” Vinther added.
Danish soldiers will be based in the Baltic region for two separate six-month spells.