At least four people have died and a further 120 have been injured in an earthquake in north-eastern Iran, the official Islamic Republic News Agency (IRNA) reported on Tuesday, citing local authorities. The United States Geological Survey (USGS) said the quake was of magnitude 4.9 and occurred at a depth of around 10 kilometres. The USGS located the epicentre near Kashmar, a city in Razavi Khorasan Province. According to the Iranian authorities, the city and its environs are home to around 160,000 people. The region, where the Arabian, Indian and Eurasian tectonic plates meet, is subject to se…