diff --git a/evm/src/get_challenges.rs b/evm/src/get_challenges.rs
index d2405b8b..d2c8e815 100644
--- a/evm/src/get_challenges.rs
+++ b/evm/src/get_challenges.rs
@@ -157,7 +157,7 @@ fn observe_block_hashes<
     for i in 0..256 {
         challenger.observe_elements(&h256_limbs::<F>(block_hashes.prev_hashes[i])[0..8]);
     }
-    challenger.observe_elements(&h256_limbs::<F>(block_hashes.cur_hash)[0..8])
+    challenger.observe_elements(&h256_limbs::<F>(block_hashes.cur_hash)[0..8]);
 }
 
 fn observe_block_hashes_target<