diff --git a/collector/requirements.txt b/collector/requirements.txt
index 15c9ca3..7009ec4 100644
--- a/collector/requirements.txt
+++ b/collector/requirements.txt
@@ -1,4 +1,4 @@
-nltk==3.1
+nltk==3.4.5
 oauthlib==1.0.3
 python-twitter==2.2
 requests==2.8.1
diff --git a/requirements.txt b/requirements.txt
index be5e593..2e5ac64 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,7 +5,7 @@ Werkzeug==0.10.4
 arrow==0.6.0
 elasticsearch==2.1.0
 itsdangerous==0.24
-nltk==3.1
+nltk==3.4.5
 oauthlib==1.0.3
 python-dateutil==2.4.2
 python-twitter==2.2