A Ukrainian national has been arrested by police in Poland as part of the investigation into the 2022 explosions that sabotaged the Nord Stream gas pipelines under the Baltic Sea, his lawyer has said.

The man, identified only as Volodymyr Z, was detained under a European arrest warrant in the early hours of Tuesday in a town near Warsaw, his lawyer told Poland’s Pap state news agency.

Several months into Russia’s full-scale invasion, three of the four Nord Stream gas pipelines from Russia to Germany were ruptured by explosives.

Mystery surrounded the blasts and no-one admitted ordering the attack. Ukraine denied involvement; Russia came under Western suspicion and Moscow blamed the US and UK.

The explosions cut off a key source of natural gas for Europe when leaders were facing an energy crisis triggered by Russia’s war, although Moscow had suspended supplies through the Nord Stream 1 pipelines, and Nord Stream 2 never started operation.

German prosecutors investigating the attack issued their first arrest warrant in August 2024, naming the man as Volodymyr Z. Reports at the time said he was a diving instructor living in Pruszkow, south-east of Warsaw, but authorities had been unable to find him.

However he was not the first suspect to be detained in the case. Another Ukrainian national called Serhii K was picked up by Italian authorities in the province of Rimini last month.

A spokesman for the Warsaw district prosecutor’s office, Piotr Antoni Skiba, told the BBC on Tuesday that proceedings had begun against a suspect from Pruszkow named as Volodymr Z.

“He is currently being investigated for the execution of a European Arrest Warrant,” the prosecutor said.

The man’s lawyer said he had been detained in the early hours of Tuesday and told Reuters news agency his extradition to Germany would be challenged as the war in Ukraine made the warrant inadmissible.

“The attack on Nord Stream infrastructure concerns one of the pipeline’s owners, Gazprom, which directly finances the military operations in Ukraine,” Tymoteusz Paprocki told Reuters.

Meanwhile, the case against Serhii K is currently going through the courts in Italy.

Accused of playing a co-ordinating role in the Nord Stream blasts, his extradition to Germany was cleared by a court in Bologna and then his lawyer appealed against the decision to Italy’s highest court of appeal.

Prosecutors believe the suspects were part of a team that sailed a yacht called Andromeda from the German port of Rostock out into the Baltic near the Danish island of Bornholm.

They said Serhii K was “strongly suspected of jointly causing an explosion and of sabotage undermining the constitution”.

German reports say seven suspects have been identified in connection with the Nord Stream blasts, although one has since died. Among the group were former members of a private diving school in Kyiv.

Germany, Denmark, and Sweden all opened investigations into the incident but the Swedish and Danish investigations closed in February without identifying any suspect.

There is no evidence so far linking Ukraine, Russia or any other state to the attacks.