The team that discovered the Baltic Sea anomaly suggested the sonar image showed an object with unusual features of seemingly non-natural origin.
Notes on verification
Directly confirmed by Wikipedia text and corroborated by independent reporting (Marine Insight, Fox News/NBC News) describing the Ocean X team's own characterization of the sonar image as unusual and seemingly non-natural.
Sources
- Baltic Sea anomaly (en.wikipedia.org)
- https://www.marineinsight.com/the-baltic-sea-mystery-of-the-strange-ufo-object/ (marineinsight.com)
- https://www.foxnews.com/science/deep-sea-baltic-ufo-hunt-turns-up-mere-rocks.amp (foxnews.com)