diff --git a/utils/build.py b/utils/build.py
index a88465d13cc6b0de706d1af6e5831deff5a0eca0..9df3408bfe74a897beb7a3bb45026eda5183bbb9 100644
--- a/utils/build.py
+++ b/utils/build.py
@@ -129,8 +129,6 @@ EXTRAS_FILES = [
 'extras/loaders/UTF8Loader.js',
 'extras/objects/Axes.js',
 'extras/objects/MarchingCubes.js',
-'extras/physics/Collisions.js',
-'extras/physics/CollisionUtils.js',
 'extras/renderers/AnaglyphWebGLRenderer.js',
 'extras/renderers/CrosseyedWebGLRenderer.js'
 ]