New intelligence has revealed that a pro-Ukraine group could be responsible for the damage and attack on the Nord Stream pipelines last year. U.S. officials say there is no evidence Ukrainian President Volodymyr Zelenskyy or his government was involved.

According to The New York Times, “the review of newly collected intelligence suggests they were opponents of President Vladimir V. Putin of Russia,” but it did not name who is in the group or who would have funded and directed the operation.

“Officials who have reviewed the intelligence said they believed the saboteurs were most likely Ukrainian or Russian nationals, or some combination of the two,” the Times reported.

What is the Nord Stream pipeline?

In September 2022, a deep sea explosion “damaged two pipes transporting Russian gas into the European Union and targeted a crucial source of revenue for Moscow,” CNN reported.

Who conducted the attack has been a mystery ever since it happened, but a portion of the U.S. intelligence community claims a pro-Ukraine group would have motive to initiate the attack “because of how Russia was weaponizing them against Ukraine and Europe,” per CNN.

Others speculated Russia could be at the center of the blame, but a motive for the Kremlin to sabotage the pipelines has not been revealed. Repairing the pipelines is estimated to start at a cost of $500 million, per the Times.

How did Ukraine respond?

An adviser to Zelenskyy, Mykhailo Podolyak, told NPR that neither Zelenskyy nor Ukraine was involved in the attack.

He told NPR the reports from The New York Times and Germany’s Di Zeit newspaper included “lots of assumptions and anonymous conjecture but not real facts.”

If Ukraine nationalists were involved, it could harm the country’s relationship with Germany, a much-needed supplier and supporter in Ukraine’s fight against Russia.

Many questions surrounding the incident remain, and officials within U.S. spy agencies and their European counterparts are still investigating, but officials did say they have more leads, per the Times.