All hell broke loose at a "Toni Braxton" concert in the Repubic of Suriname over the weekend, when the loyal TB fans realized the person on stage was a Toni Braxton imposter!

The faux-Toni, Trina Johnson, claims her contract specifically stated she was to do an "imitation act" -- and she has no idea why people thought the "real" Toni would be there.

Nevertheless, people were pissed when they found out the Braxton they thought they were gonna see wasn't really Braxton at all. According to several local reports, fans went nuts, throwing bottles on stage and even looting some of the bars at the venue.

Police have begun an investigation, but according to Caribbean Net News, the concert promoters have conveniently disappeared.

The "real" Toni Braxton's rep tells us: "Toni Braxton is aware of what happened and is obviously displeased with what happened. She regrets that both she and her fans have been victimized by this hoax. Ms. Braxton's attorneys are exploring the legal ramifications."