Police attorney said no evidence had been found linking the ship to the act, adding that while the investigation would continue, there was no reason for the vessel to remain in Tromsø any longer.
Tromso police say they seized and then released a vessel sailing between two Russian ports. Swedish and Latvian investigators are looking into the severing of an underwater cable under the Baltic Sea.
Police in Norway said on Friday they had seized a Norwegian-owned ship with a Russian crew over its suspected involvement in damage done to a Baltic Sea cable.