Natural gas from Russia to Europe via the Baltic Sea is brought to the attention of investigators.
Moscow's operator said international sanctions on Russia prevented it from carrying out vital maintenance work at the time of the leaks.
Due to Russia's invasion of Ukraine, Germany refused to certify the new Nord Stream 2 for commercial use.
Europe and Russia both said sabotage can't be ruled out, but the finger of blame is being pointed at Moscow.
For its part, Russia's state-owned gas giant Gazprom declined to comment on the leaks when approached by the news agency, while the network operator said in a statement that "the destruction that occurred on the same day simultaneously on three strings of the offshore gas pipes"
It is not possible to say when the gas transport infrastructure will be restored.
The Kremlin's spokesman said that the leak was cause for concern but that it was too early to say if it was sabotage or something else.
The Kremlin spokesman told reporters that no option can be ruled out at the moment.
It's not known if this incident is connected, but the Nord Stream 1 control center had registered a pressure drop on both strings of the gas line.
Analysts say the leaks are a huge safety and environmental hazard and maritime authorities are scrambling to figure out the extent of the problem.
There is a no-shipping zone around the location of the suspected leak in the maritime zones of the Danes and Swedes, according to a report.
BORNHOLM, DENMARK - SEPTEMBER 27: Danish Defense shows the gas leaking at Nord Stream 2 seen from the Danish F-16 interceptor on Bornholm, Denmark on September 27, 2022.The leaks will make it impossible for Europe to receive gas before winter.
The cause of the leaks is unknown, but they are rare as they are designed to prevent accidental leaks.
Several EU sources said sabotage was possible. They said that the leaks of this size are a severe safety and environmental hazard.
The leaks could lead to the permanent closing of both lines.
On Friday, Russian energy supplier Gazprom said it would not resume its supply of natural gas to Germany through the key Nord Stream 1 pipeline, blaming a malfunctioning turbine.Tensions between Russia and Europe have risen in recent months, with Russia accused of weaponizing gas supplies to its neighbor in order to get sanctions relief.
According to analysts, the stopping of gas flows to Europe was a ploy to put pressure on Europe to cave on sanctions. Experts in the gas industry andSiemens, which has provided and maintained equipment, say that the claim of sanctions preventing maintenance is false.
The allegations that Russia could be behind the damage were "remarkable" according to Timothy Ash.
There are a lot of holes in these pipes. If Russia was found to have been willing to cause such risks to shipping in the Baltics, it would be unbelievable, he said in an email.
Russia hasn't responded to accusations that it was behind the damage to the pipes.
Benchmark European gas prices increased Tuesday with Dutch TTF gas futures increasing by 8%.