The men, two dressed in traditional Afghan clothing, the other filming them, wandered down Neuhauser Strasse in downtown Munich on Saturday evening carrying a backpack with a cable hanging out of it, police reported on Tuesday.
Two of the men then approached passersby and asked them if they could help ignite the bomb.
Police were alerted at around 6.30 pm and arrested the men in a pedestrian zone in the city centre.
The men, two of whom are Afghan citizens while the third is Russian, are now being investigated for faking a crime and disturbing the public peace.
They may also have to foot the bill for the police operation, the cost of which could be several thousand euros.
According to Munich police, more and more videos are being uploaded onto the internet in which people place bomb-like devices in public places in order to scare members of the public.
“We don't find it funny at all,” a police spokesperson told the Süddeutsche Zeitung, adding that the culprits didn't seem to comprehend just how dangerous their prank was for themselves and the general public.