The system can monitor NATO's movements and has been built up with technology from companies in Sweden, Norway, the United Kingdom, and Italy. This includes communication equipment from a Swedish antenna manufacturer, according to the investigation.
Also Dagens Arbete has previously revealed that the company's products have ended up in the hands of the Russian military.
The purchases are said to have been made through a network of shell companies, including in Cyprus and Turkey.
The monitoring takes place through a network of sensors that have been placed along the seabed in the Barents Sea. Russia has previously stated that the "Harmoni" system exists, but only now can its location be pointed out.
The technology acquisitions have been made despite Western countries' sanctions, and according to SVT News, Russia has been dependent on Western technology to build up the system.
The area in question is strategically important for Russia as nuclear-armed submarines are located on the Kola Peninsula by the Barents Sea.
