Actually, he was very nice to them. It was the Dwarves who refused to cooperate, but Thranduil later became their ally and friend.

The closest equivalent to "Dark Elves" as in "Evil Elves" would have to be the Feanorians of the First Age, who willfully engaged in evil acts (the three Kin-slayings being the most well-known examples). However, as Martin points out, there are no truly evil or inherently evil Elves in Tolkien (as the D&D Drow are).

In Tolkien, Evil is achieved through personal choice or when free will is suppressed by a greater will (as with Morgoth and Sauron the way they dominate their servants).

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The LOTR/HOBBIT Movie Fact/Rumor Roundup