An earthquake has shaken the Balkan state of Montenegro. Landslides and cracks in the walls of houses occurred overnight on Wednesday, Montenegrin media reported. It was not clear whether any people were injured. According to the Institute for Hydrometeorology and Seismology in the capital Podgorica, the magnitude 5.4 quake had its epicentre near Carodja, close to Montenegro’s border with Bosnia-Herzegovina. 30 smaller tremors followed shortly afterwards. The main quake shook almost the entire Balkan peninsula and was felt as far away as Hungary to the north, according to media reports in Buda…