diff --git a/pcdet/ops/pointnet2/pointnet2_batch/src/ball_query.cpp b/pcdet/ops/pointnet2/pointnet2_batch/src/ball_query.cpp
new file mode 100644
index 0000000..c0e2d8f
--- /dev/null
+++ b/pcdet/ops/pointnet2/pointnet2_batch/src/ball_query.cpp
@@ -0,0 +1,39 @@
+/*
+batch version of ball query, modified from the original implementation of official PointNet++ codes.
+Written by Shaoshuai Shi
+All Rights Reserved 2018.
+*/
+
+
+#include <torch/serialize/tensor.h>
+#include <vector>
+#include <cuda.h>
+#include <cuda_runtime_api.h>
+#include "ball_query_gpu.h"
+
+#define CHECK_CUDA(x) do { \
+	  if (!x.type().is_cuda()) { \
+		      fprintf(stderr, "%s must be CUDA tensor at %s:%d\n", #x, __FILE__, __LINE__); \
+		      exit(-1); \
+		    } \
+} while (0)
+#define CHECK_CONTIGUOUS(x) do { \
+	  if (!x.is_contiguous()) { \
+		      fprintf(stderr, "%s must be contiguous tensor at %s:%d\n", #x, __FILE__, __LINE__); \
+		      exit(-1); \
+		    } \
+} while (0)
+#define CHECK_INPUT(x) CHECK_CUDA(x);CHECK_CONTIGUOUS(x)
+
+
+int ball_query_wrapper_fast(int b, int n, int m, float radius, int nsample, 
+    at::Tensor new_xyz_tensor, at::Tensor xyz_tensor, at::Tensor idx_tensor) {
+    CHECK_INPUT(new_xyz_tensor);
+    CHECK_INPUT(xyz_tensor);
+    const float *new_xyz = new_xyz_tensor.data<float>();
+    const float *xyz = xyz_tensor.data<float>();
+    int *idx = idx_tensor.data<int>();
+    
+    ball_query_kernel_launcher_fast(b, n, m, radius, nsample, new_xyz, xyz, idx);
+    return 1;
+}