The submarine was sighted at 6.20 pm under the Öresund Bridge, in a southerly direction, according to Sydsvenskan.

It is not confirmed which flag it has. The submarine is followed by an escort ship that is in contact with the Swedish Maritime Administration.

- It's a Russian escort ship. From a maritime safety perspective, we have contact with that ship, says Fredrik Nordanslätt at the Swedish Maritime Administration's press service.

The Swedish Maritime Administration's contact consists of ensuring that the ships follow a safe route through the Sound.

- For us at the Swedish Maritime Administration, this is a routine passage like many other ship passages, says Fredrik Nordanslätt.

SVT Nyheter is also looking for the Swedish Armed Forces for more information.

The text is updated.