diff --git a/src/main/java/cz/cvut/kbss/termit/persistence/dao/util/ScheduledContextRemover.java b/src/main/java/cz/cvut/kbss/termit/persistence/dao/util/ScheduledContextRemover.java
index fb82b4228..326fe0ab0 100644
--- a/src/main/java/cz/cvut/kbss/termit/persistence/dao/util/ScheduledContextRemover.java
+++ b/src/main/java/cz/cvut/kbss/termit/persistence/dao/util/ScheduledContextRemover.java
@@ -54,7 +54,7 @@ public synchronized void scheduleForRemoval(@NonNull URI contextUri) {
      */
     @Transactional
     @Scheduled(fixedRate = 1, timeUnit = TimeUnit.MINUTES)
-    public void runContextRemoval() {
+    public synchronized void runContextRemoval() {
         LOG.trace("Running scheduled repository context removal.");
         contextsToRemove.forEach(g -> {
             LOG.trace("Dropping repository context {}.", Utils.uriToString(g));