diff --git a/src/anomaly_detection_spatial_temporal_data/model/ncad/requirements/requirements-docs.txt b/src/anomaly_detection_spatial_temporal_data/model/ncad/requirements/requirements-docs.txt
index af1e5e8..23a0ba0 100644
--- a/src/anomaly_detection_spatial_temporal_data/model/ncad/requirements/requirements-docs.txt
+++ b/src/anomaly_detection_spatial_temporal_data/model/ncad/requirements/requirements-docs.txt
@@ -9,5 +9,5 @@ sphinx~=2.1
 sphinx-autobuild~=0.7
 sphinx-autorun
 sphinx-gallery
-tornado==5.1.1
+tornado==6.3.3
 mxtheme==0.3.*