Where do the wild parrots in Hawaii come from?

I have seen a flock of wild parrots that fly between Mt. Wai'ale'ale and Koloa an the island of Kauai on a daily basis. They feed on fruit growing on the slopes of the volcano, and return to roost in Koloa. I have heard that the origin of the flock came from a movie company that released the parrots after using them as some sort of prop in a film. The original flock numbered no more than 10-12, but the flock has grown to over 200. They are a beautiful light lime green, but I don't know specifically which species they are. Parrots on the other islands could have possibly come from the same type of source, but most likely stem from the escape of tame parrots into the wild.