(Reuters) -German investigators are examining evidence suggesting a sabotage team used Poland as an operating base to damage the Nord Stream pipelines in the Baltic Sea in September, the Wall Street Journal reported on Saturday.

The investigators have reconstructed the two-week voyage of the "Andromeda", a 50-foot (15-metre) yacht suspected of being involved in the sabotage of the Nord Stream 1 and 2 pipelines, the newspaper said.

The Journal cited people familiar with the voyage as indicating the sabotage crew had placed deep-sea explosives on Nord Stream 1, before they set the vessel on a course towards Poland. It added that Germany was trying to match DNA samples found on the vessel "to at least one Ukrainian soldier".

Germany's Federal Criminal Police Office and Poland's government spokesman did not immediately respond to requests for comment from Reuters, but one senior Polish official suggested the newspaper report was the result of Russian propaganda.

"Information about Polish or Ukrainian clues in the destruction of NS1 and NS2, repeated in the media space, is consistently used by the Russian apparatus of influence to create the impression/presumption among the recipients that Warsaw and Kiev were behind this incident," Stanislaw Zaryn, deputy to Poland's Minister Coordinator of Special Services, wrote on Twitter.

Russia's invasion of Ukraine in February 2022 put Europe's reliance on Russian natural gas in the political spotlight. The destruction of the Nord Stream pipelines hastened the region's switch to other energy suppliers.

Nord Stream 1 and Nord Stream 2, each consisting of two pipes, were built by Russia's state-controlled Gazprom to pump 110 billion cubic metres (bcm) of natural gas a year to Germany.

The Washington Post reported this week that the U.S. had learned of a Ukrainian plan to attack the pipelines three months before they were damaged by the explosions, which occurred in the economic zones of Sweden and Denmark.

Both countries said the explosions were deliberate but have yet to determine who was responsible.

German media in March identified the possible involvement of a yacht from a Poland-based company owned by Ukrainian citizens in the attack.

Ukrainian President Volodymyr Zelenskiy on Wednesday told German media Ukraine did not attack the pipelines.

(Reporting by Shivani Tanna in BengaluruAdditional reporting by Karol Badohal in WarsawEditing by William Mallard and Helen Popper)