TOKYO, Feb. 26 (Xinhua) -- An earthquake with a preliminary magnitude of 5.7 struck off the coast of Fukushima Prefecture in Japan's northeast at 1:28 a.m. local time on Monday, the weather agency here said.

While a wide swathe of Japan's eastern seaboard felt the jolt, the offshore temblor did not trigger a tsunami and the Japan Meteorological Agency (JMA) has said there is no risk of a tsunami posed by the quake.

According to the JMA, the temblor, which measured 4 on the Japanese seismic scale which peaks at 7, struck at a latitude of 37.5 degrees north and a longitude of 141.8 degrees east, and at a depth of 40 km.

The offshore quake measured 4 on the Japanese seismic scale in both the Hamadori and Nakadori regions of Fukushima Prefecture, the weather agency said.

The jolt was also felt across a swathe of Japan's eastern seaboard including Miyagi, Ibaraki, Tochigi, Gunma and Tokyo's neighboring prefectures of Chiba and Saitama, the JMA said.

Nuclear power stations in the affected regions, including the crippled Fukushima Daiichi complex, have not reported any immediate operational abnormalities as a result of the quake.

According to the latest municipal statements, there have not been any immediate reports of accident or injury to people or property as a result of the quake.