An earthquake of magnitude of 5.0 struck Tokyo and areas of eastern Japan on Wednesday morning, the US Geological Survey said.

The USGS said the quake's epicenter was east of the capital in Ibaraki at a depth of about 44km. The tremor occured at 7:25 a.m. (6.25am Singapore time)

This is the third earthquake in Tokyo in a span of four days to have rattled the capital's high-rise buildings. There were no immediate reports of damage or casualties. But the authorities said there was no threat of tsunami.

On Tuesday, a 4.8 magnitude quake hit Tokyo and on Sunday another tremor of 5.0 magnitude hit the city.

Japan is located at the junction of four tectonic plates and it experiences relatively violent quakes every year. However, the rigid building codes and strict enforcement indicate that powerful tremors frequently do little damage to the structures.