An earthquake measuring 4.6 on the Richter scale hit the town of Khoy in Iran\'s Northwestern province of West Azarbaijan on Sunday. The Seismological center of the Geophysics Institute of Tehran University registered the quake at 14:11 hours local time (1041 GMT). The epicenter of the quake is believed to have been in Eastern Turkey. A 7.2-magnitude earthquake hit just Northeast of the city of Van in Eastern Turkey near Iranian border at 1041 hours GMT (15:31 local time), causing deaths and injuries as buildings collapsed. While there are yet no reports on the number of possible casualties or damage to properties by the 4.6-magnitude quake in Northwestern Iran, early reports from Turkey said the quake killed between 500 and 1,000, injured at least 50 people and was followed by several aftershocks in the region. Within one hour, two more aftershocks of magnitude 5.6 struck the same region to the North of Van. Turkey\'s Kandilli Observatory said the death toll could be between 500 and 1,000. At least 35 buildings are reported to have collapsed. \"The quake was strongly felt in Van and neighboring towns and caused damage and deaths, based on initial assessments,\" the Turkish prime minister\'s office said. Ten buildings collapsed in Van and 25-30 in neighboring Ercis, Turkish officials said. There are people trapped under the rubble. \"There are so many dead. Several buildings have collapsed. There is too much destruction,\" Zulfikar Arapoglu, the mayor of Ercis, told NTV television. \"We need urgent aid. We need medics.\" Serious damage and casualties were reported in the district of Celebibag. The mayor, Veysel Keser, told NTV, \"There are many people under the rubble. People are in agony, we can hear their screams for help. We need urgent help. Iran\'s Red Crescent and authorities in the Iranian city of Khoy and other cities near the borders with Turkey have announced preparedness to dispatch relief and rescue teams and aid cargos. Some houses collapsed in the province of Bitlis, and in nearby Mus the quake toppled the minarets of two mosques. NTV said Van\'s airport was damaged and planes were diverted to neighboring cities. Rescue workers and residents using their bare hands and shovels struggled to free people believed to be trapped under collapsed buildings, television footage showed. Earthquakes are frequent both in Iran and Turkey because both countries sit on major geological fault lines. In Iran, the deadliest quake happened in June 1990 and measured 7.7 on the Richter scale. About 37,000 people were killed and more than 100,000 injured in the northwestern provinces of Gilan and Zanjan. It devastated 27 towns and about 1,870 villages. In Turkey, two earthquakes in 1999 with a magnitude of more than 7 killed almost 20,000 people in densely populated parts of the Northwest of the country.