The Rockland County District Attorney's Office has launched a full investigation into why a veteran police officer opened fire and killed a Spring Valley man that was described by his friends as mentally ill.

Herve Gilles, 48, was allegedly drunk, extremely violent and resisting arrest when he was fatally shot in the head and torso yesterday. Police insist there doesn't appear to be any wrongdoing on the part of the officer involved, but members of the local Haitian community who knew Gilles best say the man didn't deserve to die.

For more than 30 years, Gilles resided in Spring Valley and neighbors say his mental illness and substance abuse were no secret, but they insist he wasn't violent.

Local residents have expressed outrage, demanding to know why the officer opened fire on Gilles instead of using a Taser to subdue him.

"They want a full investigation, and that's exactly what I'm doing," says Spring Valley Mayor Norame Jasmine.

Meanwhile, Gilles' brother, Valner Romain, spoke exclusively to News 12 Hudson Valley through an interpreter, calling for an outside investigation into the fatal shooting.

Spring Valley police have yet to release the name of the officer involved in the shooting. They say they're currently interviewing witnesses.