diff --git a/Intersections_3/include/CGAL/Intersections_3/intersection_3_1_impl.h b/Intersections_3/include/CGAL/Intersections_3/intersection_3_1_impl.h
index 3eebdc99584..c44eb81f555 100644
--- a/Intersections_3/include/CGAL/Intersections_3/intersection_3_1_impl.h
+++ b/Intersections_3/include/CGAL/Intersections_3/intersection_3_1_impl.h
@@ -266,17 +266,21 @@ intersection_collinear_segments(const typename K::Segment_3 &s1,
   if ( cln_order(p,r,q) ){
     if ( cln_order(p,s,q) )
       return make_object(s2);
-    if ( cln_order(r,p,s) )
-      return r!=p ? make_object( typename K::Segment_3(r,p) ) : make_object(p);
-    else
-      return r!=q ? make_object( typename K::Segment_3(r,q) ) : make_object(q);
+    if ( cln_order(r,p,s) ){
+      if (r!=p) return make_object( typename K::Segment_3(r,p) );
+      if ( cln_order(r,q,s) ) return make_object(s1);
+      return make_object(p);
+    }
+    return r!=q ? make_object( typename K::Segment_3(r,q) ) : make_object(q);
   }
 
   if ( cln_order(p,s,q) ){
-    if ( cln_order(r,p,s) )
-      return s!=p ? make_object( typename K::Segment_3(s,p) ) : make_object(p);
-    else
-      return s!=q ? make_object( typename K::Segment_3(s,q) ) : make_object(q);
+    if ( cln_order(r,p,s) ){
+      if (s!=p) return make_object( typename K::Segment_3(s,p) );
+      if (cln_order(r,q,s)) return make_object(s1);  
+      return make_object(p);
+    }
+   return s!=q ? make_object( typename K::Segment_3(s,q) ) : make_object(q);
   }
   
   if ( cln_order(r,p,s) )
diff --git a/Intersections_3/test/Intersections_3/segment_segment.cpp b/Intersections_3/test/Intersections_3/segment_segment.cpp
index 4a42c464774..fecf2b873f1 100644
--- a/Intersections_3/test/Intersections_3/segment_segment.cpp
+++ b/Intersections_3/test/Intersections_3/segment_segment.cpp
@@ -9,6 +9,87 @@ typedef CGAL::Cartesian<FT>                                 K;
 // The construction test has to be working
 // The equal test has to be working
 
+#define TEST_CASE_SEGMENT_BASE(i,j,k,l,i1,i2) \
+{\
+  typename K::Segment_3 s1(pts[i],pts[j]); \
+  typename K::Segment_3 s2(pts[k],pts[l]); \
+  CGAL::Object obj= CGAL::intersection(s1,s2); \
+  typename K::Segment_3 s; \
+  typename K::Segment_3 res(pts[i1],pts[i2]);\
+  if (!CGAL::assign(s,obj) || ( s!=res && s!=res.opposite() )  ) {\
+    std::cerr << "ERROR test-case "<< i << j << k <<l <<std::endl; \
+    exit (EXIT_FAILURE);\
+  }\
+}
+
+#define TEST_CASE_SEGMENT(i,j,k,l,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(i,j,k,l,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(j,i,k,l,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(i,j,l,k,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(j,i,l,k,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(k,l,i,j,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(k,l,j,i,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(l,k,i,j,i1,i2) \
+  TEST_CASE_SEGMENT_BASE(l,k,j,i,i1,i2) 
+  
+#define TEST_CASE_POINT_BASE(i,j,k,l,ind) \
+{\
+  typename K::Segment_3 s1(pts[i],pts[j]); \
+  typename K::Segment_3 s2(pts[k],pts[l]); \
+  CGAL::Object obj= CGAL::intersection(s1,s2); \
+  typename K::Point_3 p; \
+  if (!CGAL::assign(p,obj) || p!=pts[ind] ) {\
+    std::cerr << "ERROR test-case "<< i << j << k <<l <<std::endl; \
+    exit (EXIT_FAILURE);\
+  }\
+}
+
+#define TEST_CASE_POINT(i,j,k,l,ind) \
+  TEST_CASE_POINT_BASE(i,j,k,l,ind) \
+  TEST_CASE_POINT_BASE(j,i,k,l,ind) \
+  TEST_CASE_POINT_BASE(i,j,l,k,ind) \
+  TEST_CASE_POINT_BASE(j,i,l,k,ind) \
+  TEST_CASE_POINT_BASE(k,l,i,j,ind) \
+  TEST_CASE_POINT_BASE(k,l,j,i,ind) \
+  TEST_CASE_POINT_BASE(l,k,i,j,ind) \
+  TEST_CASE_POINT_BASE(l,k,j,i,ind)
+  
+
+#define TEST_CASE_EMPTY_BASE(i,j,k,l) \
+{\
+  typename K::Segment_3 s1(pts[i],pts[j]); \
+  typename K::Segment_3 s2(pts[k],pts[l]); \
+  CGAL::Object obj= CGAL::intersection(s1,s2); \
+  if ( !obj.empty() ) {\
+    std::cerr << "ERROR test-case "<< i << j << k <<l <<std::endl; \
+    exit (EXIT_FAILURE);\
+  }\
+}
+
+#define TEST_CASE_EMPTY(i,j,k,l) \
+  TEST_CASE_EMPTY_BASE(i,j,k,l)\
+  TEST_CASE_EMPTY_BASE(i,j,l,k)\
+  TEST_CASE_EMPTY_BASE(j,i,k,l)\
+  TEST_CASE_EMPTY_BASE(j,i,l,k)\
+  TEST_CASE_EMPTY_BASE(k,l,i,j)\
+  TEST_CASE_EMPTY_BASE(l,k,i,j)\
+  TEST_CASE_EMPTY_BASE(k,l,j,i)\
+  TEST_CASE_EMPTY_BASE(l,k,j,i)
+
+template <class K>
+void all_cases_collinear(typename K::Point_3 pts[4]){
+  std::cout << "4 points cases\n";
+  TEST_CASE_EMPTY(0,1,2,3)
+  TEST_CASE_SEGMENT(0,2,1,3,1,2)
+  TEST_CASE_SEGMENT(0,3,2,1,1,2)
+  std::cout << "3 points cases\n";
+  TEST_CASE_SEGMENT(0,1,0,2,0,1)
+  TEST_CASE_SEGMENT(0,2,1,2,1,2)
+  TEST_CASE_POINT(1,2,0,1,1)
+  std::cout << "2 points cases\n";
+  TEST_CASE_SEGMENT(1,2,1,2,1,2)
+}
+
 template <class K>
 void _test_intersection_construct(K)
 {
@@ -68,5 +149,9 @@ int main()
 {
   K k;
   _test_intersection_construct(k);
+  
+   
+  K::Point_3 pts[4] = {K::Point_3(0,0,0),K::Point_3(1,0,0),K::Point_3(2,0,0),K::Point_3(3,0,0)};
+  all_cases_collinear<K>(pts);
   return 0;
 }