July 4 (IANS) An earthquake with a preliminary magnitude of 5.4 on Thursday struck Chiba prefecture, just east of Tokyo, said the country's weather agency. The temblor occurred at around 12.12 p.m. local time at a depth of 50 km, measuring 4 on the Japanese seismic intensity scale of 7, the Japan Meteorological Agency said, adding that there was no threat of a tsunami, reported Xinhua news agency. The epicentre was located off eastern Chiba prefecture at a latitude of 35.2 degrees north and a longitude of 140.5 degrees east. Tremors were felt in all 23 wards of Tokyo, with no immediate reports of injuries or major damage.