Here’s a lesson on how to get revenge on your bank.

What this furious FNB customer did has gone viral on Social Media, after displaying a banner declaring the institution to be “Flippen Negligent Bankers” over the Johannesburg highway.

The bank’s logo has been replaced by an AK-47 assault rifle.

This is possibly in response to the loss of two high-profile safety deposit box in robberies.

As no one has come forward claiming responsibility for the sign however, it is difficult to say whether the two are related or if the customer is disgruntled for other reasons.