Offensive images have been displayed on a Cardiff city centre billboard, prompting a police investigation.
Swastikas and far-right images were displayed on the Queen Street screen on Tuesday night after a hacker gained control and selected what was shown.
Writing in an anonymous online post, the hacker claimed there was a security vulnerability with the screens.
BlowUP media, who controls the billboard, has been contacted for comment.
South Wales Police said it had received a number of calls relating to the incident.
A spokesman added: “We alerted the city council and will investigate any crimes which may have been committed.”