diff --git a/nestkernel/node_collection.cpp b/nestkernel/node_collection.cpp
index f3be96c75c..b4323921f4 100644
--- a/nestkernel/node_collection.cpp
+++ b/nestkernel/node_collection.cpp
@@ -1337,9 +1337,11 @@ NodeCollectionComposite::get_nc_index( const size_t node_id ) const
     }
   }
 
-  assert( lower == upper );
+  // If node_id is not in the NodeCollection, lower may pass upper in the loop above
+  // See test_regression_issue-3213.py for an example case.
+  assert( lower >= upper );
 
-  if ( node_id < parts_[ lower ][ 0 ] or parts_[ lower ][ parts_[ lower ].size() - 1 ] < node_id )
+  if ( lower > upper or node_id < parts_[ lower ][ 0 ] or parts_[ lower ][ parts_[ lower ].size() - 1 ] < node_id )
   {
     // node_id is in a gap of nc
     return -1;
diff --git a/testsuite/pytests/sli2py_mpi/README.md b/testsuite/pytests/sli2py_mpi/README.md
index cb48da01fc..6f9abee576 100644
--- a/testsuite/pytests/sli2py_mpi/README.md
+++ b/testsuite/pytests/sli2py_mpi/README.md
@@ -2,4 +2,4 @@
 
 Test in this directory run NEST with different numbers of MPI ranks and compare results.
 
-See documentation in mpi_test_wrappe.py for details.
+See documentation in mpi_test_wrapper.py for details.
diff --git a/testsuite/pytests/test_regression_issue-3213.py b/testsuite/pytests/test_regression_issue-3213.py
new file mode 100644
index 0000000000..2e13f9aac7
--- /dev/null
+++ b/testsuite/pytests/test_regression_issue-3213.py
@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+#
+# test_regression_issue-3213.py
+#
+# This file is part of NEST.
+#
+# Copyright (C) 2004 The NEST Initiative
+#
+# NEST is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#
+# NEST is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with NEST.  If not, see <http://www.gnu.org/licenses/>.
+
+import nest
+import pytest
+
+"""
+Test that GetConnections works if NodeCollection with gaps is provided as source arg.
+"""
+
+
+def test_get_conns_works():
+    """Main concern is that GetConnections() passes, expected number of connections based on all-to-all."""
+
+    num_n = 12
+    n = nest.Create("parrot_neuron", num_n)
+    nest.Connect(n, n)
+    pick = [3, 7, 9, 11]
+    conns = nest.GetConnections(source=n[pick])
+    assert len(conns) == num_n * len(pick)