MILAN — Russia’s detention of a Greek-owned ship that departed from Estonia – days after Estonian forces tried to intercept a Russia-bound tanker – signals Moscow’s willingness to deploy military power more overtly to protect its shadow-fleet, a vital pillar of its war economy, experts say.

Russia detained a Greek-owned oil tanker on Sunday after it left an Estonian Baltic Sea port, the Estonian Foreign Ministry said, adding it had alerted NATO allies to the incident.

Russia detained the Liberian-flagged oil tanker Green Admire, which left the port of Sillamae and was sailing through Russian territorial waters, Estonian Public Broadcasting said Sunday, citing the Estonian Department of Transport.