On Friday, amid a lot of traffic on a street in Jakarta, a pornographic film started playing on a video billboard, setting Indonesian social media ablaze. 

The movie, which appeared to be Japanese, carried on for five minutes, before police were able to cut off the power.

And initially it seemed likely to be a (relatively) harmless prank, something to light up an idle Friday.

But then the police got involved. And, according to the Associated Press, they have seized computers and launched a full investigation. Jail time and fines are on the line, if anyone should be found directly responsible for the stunt. The police haven’t named any suspects, but they’ve so far spoken to nearly a dozen people from the company that owns the billboard.

Still, the company says they have a simple explanation for what went down: a hacker, who they say took over their computer systems. Which may seem unlikely, but has indeed happened before.