In the early hours of Sunday 8 October, pressure at the Balticconnector gas pipeline between Estonia and Finland suddenly started to drop.
There was a heavy storm that weekend, but when the authorities were finally able to investigate the seabed, they discovered traces of something being dragged along the bottom, a torn pipeline and a broken anchor.
A data cable dozens of miles to the east was torn in half. Another cable that connects Estonia and Sweden was also malfunctioning. Similar traces to the pipeline site were found in both these locations.
The prime suspect of these incidents is the Chinese cargo vessel Newnew Polar Bear, which passed each location around the time the damage took place. A photo taken a few days later shows Newnew Polar Bear missing an anchor and its containers tilting heavily to one side.
The ship’s crew has refused to respond to investigators’ inquiries. It is not clear if an actor caused the damages knowingly or accidentally, but the incident indicates how easy it is to sabotage critical undersea infrastructure.
Although the Balticconnector will be out of service until at least April next year, the two countries’ energy supplies are safe. But NATO has stepped up surveillance of the Baltic Sea area to prevent further incidents.