diff --git a/tools/releasetools/img_from_target_files b/tools/releasetools/img_from_target_files
index 488226f..793f7ac 100755
--- a/tools/releasetools/img_from_target_files
+++ b/tools/releasetools/img_from_target_files
@@ -63,9 +63,11 @@
   build_command = []
   fstab = OPTIONS.info_dict["fstab"]
   if fstab and fstab["/data"].fs_type.startswith("ext"):
-    build_command = ["mkuserimg.sh",
-                     user_dir, img.name,
-                     fstab["/data"].fs_type, "data"]
+    build_command = ["mkuserimg.sh"]
+    if "extfs_sparse_flag" in OPTIONS.info_dict:
+      build_command.append(OPTIONS.info_dict["extfs_sparse_flag"])
+    build_command.extend([user_dir, img.name,
+                     fstab["/data"].fs_type, "data"])
     if "userdata_size" in OPTIONS.info_dict:
       build_command.append(str(OPTIONS.info_dict["userdata_size"]))
   else:
@@ -112,9 +114,12 @@
   build_command = []
   fstab = OPTIONS.info_dict["fstab"]
   if fstab and fstab["/system"].fs_type.startswith("ext"):
-    build_command = ["mkuserimg.sh",
-                     os.path.join(OPTIONS.input_tmp, "system"), img.name,
-                     fstab["/system"].fs_type, "system"]
+
+    build_command = ["mkuserimg.sh"]
+    if "extfs_sparse_flag" in OPTIONS.info_dict:
+      build_command.append(OPTIONS.info_dict["extfs_sparse_flag"])
+    build_command.extend([os.path.join(OPTIONS.input_tmp, "system"), img.name,
+                     fstab["/system"].fs_type, "system"])
     if "system_size" in OPTIONS.info_dict:
       build_command.append(str(OPTIONS.info_dict["system_size"]))
   else: