A large crowd was seen gathering around the billboard, in Malmö Central Station, which began showing porn clips from Meatspin.
The public transport operator, Skånetrafiken, told the Swedish newspaper Aftonbladet that it had not received complaints that their screens or information boards had suffered from malfunctions.
Reklamskylt visade grov porr på stationen https://t.co/95sGRuTUEE pic.twitter.com/ReuC7IBT0H
— Kvällsposten (@Kvallsposten) May 8, 2016
A spokesman for Skånetrafiken told the tabloid: "So far, we regard it as a prank, but nevertheless we regret it. Such things should not be."
It is understood the breach targeted the servers of Global Agencies, the agency which handles the advertisement boards in Malmö.
Roger Starck of Global Agencies referred to a hacker attack and described the incident as "very serious".
