diff --git a/src/CBot/CBotClass.cpp b/src/CBot/CBotClass.cpp
index 579dda03..13fb8379 100644
--- a/src/CBot/CBotClass.cpp
+++ b/src/CBot/CBotClass.cpp
@@ -455,7 +455,8 @@ CBotClass* CBotClass::Compile1(CBotToken* &p, CBotCStack* pStack)
     std::string name = p->GetString();
 
     CBotClass* pOld = CBotClass::Find(name);
-    if ( pOld != nullptr && pOld->m_IsDef )
+    if ( (pOld != nullptr && pOld->m_IsDef) ||          /* public class exists in different program */
+         pStack->GetProgram()->ClassExists(name))       /* class exists in this program */
     {
         pStack->SetError( CBotErrRedefClass, p );
         return nullptr;
@@ -489,14 +490,13 @@ CBotClass* CBotClass::Compile1(CBotToken* &p, CBotCStack* pStack)
         }
 
         int level = 1;
-        do                                          // skip over the definition
+        while (level > 0 && p != nullptr)
         {
             int type = p->GetType();
             p = p->GetNext();
             if (type == ID_OPBLK) level++;
             if (type == ID_CLBLK) level--;
         }
-        while (level > 0 && p != nullptr);
 
         if (level > 0) pStack->SetError(CBotErrCloseBlock, classe->m_pOpenblk);
 
diff --git a/src/CBot/CBotProgram.cpp b/src/CBot/CBotProgram.cpp
index dce62198..32813de1 100644
--- a/src/CBot/CBotProgram.cpp
+++ b/src/CBot/CBotProgram.cpp
@@ -281,6 +281,16 @@ const std::list<CBotFunction*>& CBotProgram::GetFunctions()
     return m_functions;
 }
 
+bool CBotProgram::ClassExists(std::string name)
+{
+    for (CBotClass* p : m_classes)
+    {
+        if ( p->GetName() == name ) return true;
+    }
+
+    return false;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 CBotTypResult cSizeOf( CBotVar* &pVar, void* pUser )
 {
diff --git a/src/CBot/CBotProgram.h b/src/CBot/CBotProgram.h
index d90fb0ef..4a64b562 100644
--- a/src/CBot/CBotProgram.h
+++ b/src/CBot/CBotProgram.h
@@ -333,6 +333,12 @@ public:
      */
     const std::list<CBotFunction*>& GetFunctions();
 
+    /**
+     * \brief Check if class with that name was created in this program
+     * \return True if class was defined in this program, otherwise, false
+     */
+    bool ClassExists(std::string name);
+
     /**
      * \brief Returns static list of all registered external calls
      */
diff --git a/test/unit/CBot/CBot_test.cpp b/test/unit/CBot/CBot_test.cpp
index 0dae25e0..6cf28413 100644
--- a/test/unit/CBot/CBot_test.cpp
+++ b/test/unit/CBot/CBot_test.cpp
@@ -932,8 +932,19 @@ TEST_F(CBotUT, ClassMethodRedefined)
     );
 }
 
-// TODO: Not only doesn't work but segfaults
-TEST_F(CBotUT, DISABLED_ClassRedefined)
+TEST_F(CBotUT, ClassRedefinedInDifferentPrograms)
+{
+    auto publicProgram = ExecuteTest(
+        "public class TestClass {}\n"
+    );
+
+    ExecuteTest(
+        "public class TestClass {}\n",
+        CBotErrRedefClass
+    );
+}
+
+TEST_F(CBotUT, ClassRedefinedInOneProgram)
 {
     ExecuteTest(
         "public class TestClass {}\n"
@@ -942,6 +953,15 @@ TEST_F(CBotUT, DISABLED_ClassRedefined)
     );
 }
 
+TEST_F(CBotUT, ClassMissingCloseBlock)
+{
+    ExecuteTest(
+        "public class Something\n"
+        "{\n",
+        CBotErrCloseBlock
+    );
+}
+
 // TODO: NOOOOOO!!! Nononononono :/
 TEST_F(CBotUT, DISABLED_PublicClasses)
 {