Japan was yet again rattled by a 7.4 magnitude earthquake, Thursday night. A tsunami warning was immediately announced after the quake was felt.

Broadcasters of Japan’s public news network told people living in the northeastern shore of the country to evacuate to higher grounds and as far away from the shore as possible. One hour after the quake hit Japan, no tsunami was observed hitting the shore.

Officials of Fukushima Dai-ichi nuclear plant (a nuclear plant that is still managing the damages caused by the previous tsunami that hit Japan barely a month ago) said that they see no immediate signs of additional problems from the recent quake. No one in the plant was injured as the workers were immediately relocated to a quake-resistant area inside the complex.

Government officials said that the aftershock hit 50 kilometers off the coast of Miyagi prefecture. Buildings in Tokyo shook for as long as a minute. In Ichinoseki, a place closer to the Miyagi prefecture compared to Tokyo, shelves and furniture were knocked out. Right after the quake, electrical supply to that area was cut to prevent accidental fires.

The earthquake shook Japan at 11:32 in the evening, local time. A little earlier than that, Japanese TV already announced a warning for a possible quake and loudspeakers warned residents of the western suburbs in Tokyo.

Experts are not expecting an ocean-wide tsunami but they emphasized that quakes that strong may cause local waves that can cause vast damages.

The Obama administration is setting up more radiation monitors on the state of Hawaii, as well as on other islands covered by the United States, the environmental regulators informed on Tuesday.

The government is deploying radiation detectors on the islands even though it is not expecting harmful radiation levels coming from the quake-hit nuclear power plants in Japan to reach the soils of United States.

A notice was posted on the website of the Environmental Protection Agency on Tuesday, saying it has plans to collaborate with federal agencies to put additional radiation detectors on the western part of the United States and other U.S. territories.

An official from EPA said that there were already seven monitors being deployed to three U.S. islands. Three monitors were sent to Aleutian Islands in Alaska and two monitors each to Hawaii and Guam. According to the official, the monitors were sent “in an abundance of caution.”

The EPA official, who refused to be named, also said that the agency has 40 more detectors that could be dispatched. These detectors will enhance the several monitors already installed in the entire 50 states of U.S., a Democratic congressional said.

Japan has been trying to deal with the damage done on the nuclear power plants since the earthquake and tsunami has hit the country on Friday. U.S. officials have already advised many American citizens around the area of the Fukushima nuclear complex to evacuate as soon as possible.

However, U.S. officials are not expecting any harmful radiation from the devastated country to reach the borders of the United States. Still, EPA will continue tracking the radiation levels from the radiation detectors through its Internet database.