European countries are investigating three mystery leaks in two major gas pipelines between Russia and Europe.
The cause of the damage to Nord Stream 1 and 2 is unclear, but authorities have not ruled out sabotage.
The operator of Nord Stream 1 said the undersea lines had simultaneously sustained “unprecedented” damage in one day.
Both pipelines have been flashpoints in the energy tussle between Moscow and Europe.
Whatever the cause of the damage, it won’t immediately affect the gas supply to Europe as neither pipeline was operational.
The European Union has previously accused Russia of using a reduction in gas supplies to blackmail Europe, but Moscow denies this. It says sanctions against Russia make it impossible to maintain the gas infrastructure properly.
Unconfirmed reports in German media said authorities are not ruling out an attack on the undersea gas network.
Denmark’s Prime Minister, Mette Frederiksen, said it was too early to come to conclusions but that it was hard to imagine the multiple leaks could be a coincidence.
A Kremlin spokesperson, Dmitry Peskov, said he was “extremely concerned” about the incident and could not rule out the possibility of a deliberate attack.
Although neither pipelines are in operation, they both still contain gas.
German, Danish, and Swedish authorities are all investigating the incidents.
The operators of Nord Stream 2 warned of a loss of pressure in the pipeline on Monday afternoon. That led to a warning from Danish authorities that ships should avoid the area near the island of Bornholm.
There are growing fears families in the EU will be unable to afford the cost of heating this winter.
Poland is leading the effort to curb reliance on Russia, once Europe’s main energy supplier, with the inauguration of a new gas pipeline.
The Baltic Pipe will be a new link for Norwegian gas to Europe, allowing countries south of Poland, including Slovakia and the Czech Republic, to access it.