diff --git a/src/SIL.Machine/Corpora/UsfmTokenizer.cs b/src/SIL.Machine/Corpora/UsfmTokenizer.cs
index 32ba32fd..c03b836d 100644
--- a/src/SIL.Machine/Corpora/UsfmTokenizer.cs
+++ b/src/SIL.Machine/Corpora/UsfmTokenizer.cs
@@ -385,7 +385,16 @@ public IReadOnlyList<UsfmToken> Tokenize(string usfm, bool preserveWhitespace =
                         else if (tokens[i - 1].Type == UsfmTokenType.End)
                         {
                             // Insert space token after * of end marker
-                            int colNum = usfm.Length + 1 - Math.Max(usfm.LastIndexOf('\n', index), 0);
+                            int colNum;
+                            if (index >= usfm.Length)
+                            {
+                                colNum = usfm.Length + 1;
+                            }
+                            else
+                            {
+                                colNum = usfm.Length + 1 - Math.Max(usfm.LastIndexOf('\n', index), 0);
+                            }
+
                             tokens.Insert(
                                 i,
                                 new UsfmToken(UsfmTokenType.Text, null, " ", null)
diff --git a/tests/SIL.Machine.Tests/Corpora/UsfmTokenizerTests.cs b/tests/SIL.Machine.Tests/Corpora/UsfmTokenizerTests.cs
index 6137246a..d77c9035 100644
--- a/tests/SIL.Machine.Tests/Corpora/UsfmTokenizerTests.cs
+++ b/tests/SIL.Machine.Tests/Corpora/UsfmTokenizerTests.cs
@@ -47,6 +47,19 @@ public void Detokenize()
         Assert.That(result, Is.EqualTo(usfm));
     }
 
+    [Test]
+    public void Tokenize_Ending_ParagraphMarker()
+    {
+        //The ending paragraph marker should not crash the parser.
+        string usfm =
+            @"\id MAT - Test
+\c 1
+\v 1 Descriptive title\x - \xo 18:16 \xt  hello world\x*\p
+";
+        IReadOnlyList<UsfmToken> tokens = new UsfmTokenizer().Tokenize(usfm);
+        Assert.That(tokens, Has.Count.EqualTo(13));
+    }
+
     private static string ReadUsfm()
     {
         return File.ReadAllText(Path.Combine(CorporaTestHelpers.UsfmTestProjectPath, "41MATTes.SFM"));