At about 3am the Russian Border Guard unilaterally removed the light buoys with which Estonia marks the course of the border on the Narva river. The Estonian foreign ministry called it a provocative border incident and demanded an explanation and the return of the buoys. The statement does not give their number. Russia offered no explanation.
Responsibility and limits of the evidence
officially attributed
A court or a competent state body has attributed it. That is not the same as a proven attack: an indictment is an allegation, not a verdict.
Named party: Russian Federation Border Guard
B - official attribution by a state body
Ministerstwo Spraw Zagranicznych Estonii / 2024-05-23 / carrying out the act
The Estonian foreign ministry stated that the buoys were removed by the Russian Border Guard and demanded their return. The actor here is a state formation acting openly, not an unidentified operator.