[1] Reports of new submarine sightings and television imagery of Swedish Navy helicopters firing depth charges into coastal waters against suspected intruders became commonplace in the mid-to-late 1980s.
The Soviet Union consistently denied that it was responsible for violating Swedish waters, and claimed that the U 137 had only crossed the border because of navigational faults.
[37] In 1984 a Finn living in Sweden published the satirical Finnish novel Probable Submarine (Todennäköinen sukellusvene) under the pen-name Klaus Viking.
The novel is an examination of Swedish culture and politics as seen through the eyes of a Finnish immigrant who takes it upon himself to create some excitement by constructing a sham submarine and towing it through a restricted military area of the archipelago.
It reflects a certain degree of amusement with which some segments of Sweden's neighbor populations regarded the country's recurrent searches for submarine violations of its territorial integrity.