diff --git a/src/Base/Tools.cpp b/src/Base/Tools.cpp
index 29d2f96ed2fb..8957f0c12622 100644
--- a/src/Base/Tools.cpp
+++ b/src/Base/Tools.cpp
@@ -30,6 +30,7 @@
 
 # include <QTime>
 #include "PyExport.h"
+#include "Interpreter.h"
 #include "Tools.h"
 
 namespace Base {
@@ -144,17 +145,28 @@ std::string Base::Tools::narrow(const std::wstring& str)
 
 std::string Base::Tools::escapedUnicodeFromUtf8(const char *s)
 {
+    Base::PyGILStateLocker lock;
+    std::string escapedstr;
+
     PyObject* unicode = PyUnicode_FromString(s);
+    if (!unicode)
+        return escapedstr;
+
     PyObject* escaped = PyUnicode_AsUnicodeEscapeString(unicode);
+    if (escaped) {
+        escapedstr = std::string(PyString_AsString(escaped));
+        Py_DECREF(escaped);
+    }
+
     Py_DECREF(unicode);
-    std::string escapedstr = std::string(PyString_AsString(escaped));
-    Py_DECREF(escaped);
     return escapedstr;
 }
 
 std::string Base::Tools::escapedUnicodeToUtf8(const std::string& s)
 {
+    Base::PyGILStateLocker lock;
     std::string string;
+
     PyObject* unicode = PyUnicode_DecodeUnicodeEscape(s.c_str(), s.size(), "strict");
     if (!unicode)
         return string;