diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 2571e4203..093f9f779 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -890,6 +890,7 @@ difficulty_type Blockchain::get_difficulty_for_next_block()
 //------------------------------------------------------------------
 std::vector<time_t> Blockchain::get_last_block_timestamps(unsigned int blocks) const
 {
+  CRITICAL_REGION_LOCAL(m_blockchain_lock);
   uint64_t height = m_db->height();
   if (blocks > height)
     blocks = height;