When asked about the possible causes of sudden pressure loss in three of the Baltic Sea gas network's lines, Kremlin Spokesperson Dmitry Peskov suggested that the Nord Stream pipelines had been damaged in an act of sabotage.

In a press conference on Tuesday, Peskov commented on a statement issued by Nord Stream AG, the network's operator, saying that three offshore lines of the Nord Stream pipeline system sustained "unprecedented" damage in just one day.

“No option can be ruled out right now,” Peskov said when asked if the damage may have been the result of sabotage. He added that Moscow is very concerned about the situation and called for an immediate and thorough investigation into the incident, which has implications for energy security on the “entire continent".

Line A of the Nord Stream 2 pipeline held pressure that was pumped with gas but had yet to go into operation, suddenly dropping overnight between Sunday and Monday. Shortly after that, both of Nord Stream 1’s pipelines also suffered a sharp loss of pressure. 

Since then, the coastguards of Sweden and Denmark have reported gas leaks off the coast of Bornholm island in the Baltic Sea, one in the Swedish economic zone and one in the Danish zone, and the area has been closed to maritime traffic. 

Berlin believes the sudden pressure drop in three gas pipelines at the same time could not be a coincidence and is likely a “targeted attack” from either Ukraine or Russia, according to a report from the Tagesspiegel newspaper on Tuesday.

A deliberate attack on the pipeline could only be carried out by special forces, navy divers, or a submarine, according to the outlet. Berlin believes the sabotage was carried out by "Ukraine-affiliated forces" or by Russia itself as a "false flag" operation to make Ukraine look bad and drive up EU energy prices.

Underwater explosions reported

The Swedish National Seismic Network (SNSN) reported powerful underwater explosions in the area of gas leaks from the Nord Stream pipeline on Tuesday.

SNSN Director Bjorn Lund said as quoted by SVT that "there are no doubts that these were explosions."

“One explosion had a magnitude of 2.3 and was registered by dozens of monitoring stations in southern Sweden,” he stated.

“You can clearly see the waves bounce from the bottom to the surface," Lund added.

On his part, Peter Schmidt, an Uppsala University seismologist, said the Swedish National Seismic Network recorded two "massive releases of energy" shortly prior to, and near the location of, the gas leaks off the coast of the Danish island of Bornholm.

"The first happened at 2:03 am (0003 GMT) just southeast of Bornholm with a magnitude of 1.9. Then we also saw one at 7:04 pm on Monday night, another event a little further north and that seems to have been a bit bigger. Our calculations show a magnitude of 2.3," Schmidt said.

The Norwegian Seismic Array (NORSAR) also confirmed it had registered "a smaller explosion" in the early hours of Monday, "followed by a more powerful one on Monday evening."

Photos taken by the Danish military on Tuesday showed large masses of bubbles on the surface of the water emanating from the three leaks located in Sweden's and Denmark's economic zones, spreading from 200 to 1,000 meters (656 feet to 0.62 miles) in diameter.

Earlier today, Denmark's maritime traffic agency and Sweden's Maritime Authority on Monday reported a "dangerous" gas leak in the Baltic Sea close to the route of the inactive Nord Stream 2 pipeline, which experienced an unexplained drop in pressure.

The leak, southeast of the Danish island of Bornholm, "is dangerous for maritime traffic" and "navigation is prohibited within a five nautical mile radius of the reported position," the agency warned in a notice to ships.