The gang can be seen on some early screenshots of GTA III. They have bandanas with a flag on their heads or regular bandanas, similiar to the ones which the Diablos wear, and have dark blue cloth-jackets, jeans shorts with green ends and a white stripe with black stars on them and black-white sneakers. On one screenshot they can be seen carrying a Baseball Bat and standing near a Hum Vee, the beta Patriot.
Possible final version
Judging from the images and the locations of them, this gang could have been a beta idea for BOTH gangs at different points in development, or just the one gang with experimental ideas for territory. Which might be the reason we see this beta design in what is now the current Diablo and Triad areas.