diff --git a/src/aleph/web/controllers/messages.py b/src/aleph/web/controllers/messages.py
index b8630891e..f06f4a6bf 100644
--- a/src/aleph/web/controllers/messages.py
+++ b/src/aleph/web/controllers/messages.py
@@ -83,12 +83,14 @@ def validate_field_dependencies(cls, values):
 
     @validator(
         "addresses",
+        "refs",
         "content_hashes",
         "content_keys",
         "content_types",
         "chains",
         "channels",
         "tags",
+        "hashes",
         pre=True,
     )
     def split_str(cls, v):
diff --git a/tests/api/test_messages.py b/tests/api/test_messages.py
index bd07f449c..81d97aa70 100644
--- a/tests/api/test_messages.py
+++ b/tests/api/test_messages.py
@@ -132,6 +132,18 @@ async def test_get_messages_filter_by_content_hash(fixture_messages, ccn_api_cli
     )
 
 
+@pytest.mark.asyncio
+async def test_get_messages_multiple_hashes(fixture_messages, ccn_api_client):
+    hashes = [
+        "2953f0b52beb79fc0ed1bc455346fdcb530611605e16c636778a0d673d7184af",
+        "bc411ae2ba89289458d0168714457e7c9394a29ca83159240585591f4f46444a",
+    ]
+    response = await ccn_api_client.get(MESSAGES_URI, params={"hashes": ",".join(hashes)})
+    assert response.status == 200, await response.text()
+    messages = (await response.json())["messages"]
+    assert len(messages) == 2
+
+
 @pytest.mark.asyncio
 async def test_get_messages_filter_by_invalid_content_hash(
     fixture_messages, ccn_api_client