During the exercise, coast guard, police and military personnel fast-roped from a helicopter onto a vessel, took control of its crew and searched the ship room by room.
Coast Guard Commander Ilja Iljin, who led the exercise, said such operations are becoming part of Finland’s “new normal.”
“In the past two or three years we’ve had several incidents in the Baltic related to the damaging of critical underwater infrastructure,” Iljin said. “So we have to be ready for when the next event happens.”
Authorities may become suspicious of a vessel if it behaves unusually while passing over an undersea cable, including by abruptly slowing down or unexpectedly changing course, Iljin said.
Finland has progressively shortened its response time following previous incidents involving damaged infrastructure.
Police special intervention units can assemble at their base within an hour before deploying by helicopter or boat in a real emergency, according to Chief Inspector Juha Hietala.
While several recent incidents have involved ships dragging their anchors, Finnish authorities are also preparing for more deliberate forms of sabotage involving divers, mini-submarines or underwater drones carrying explosives.
Finland is separately seeking to expand the Border Guard’s authority to stop and inspect vessels suspected of sailing without a valid national flag or under a false flag, as well as to intervene against unmanned underwater vehicles.
MARSEC EU 26 focuses on critical infrastructure
The practical phase of the MARSEC EU 26 exercise was held in Finland on Sept. 15-17.
Participants simulated an incident involving a suspicious vessel near critical underwater infrastructure and practiced boarding, searching and taking control of the ship.
The Finnish Border Guard organized the exercise with partners from the European Union.
Particular attention was given to protecting undersea cables and pipelines against potential hybrid threats.
Finland and other Baltic Sea countries have stepped up protection of critical infrastructure after a series of incidents involving damaged power cables, telecommunications links and gas pipelines in recent years.
Finland has previously detained vessels suspected of involvement in damage to undersea infrastructure.
Russian involvement has not been established in all such cases, and Moscow has denied responsibility for incidents attributed to it.