Temblors thought to be aftershocks of the Great East Japan Earthquake have rocked the Tohoku and Kanto regions at more than twice the pre-3/11 rate in the past year, according to the government’s Earthquake Research Committee.

Figures released by the committee on March 9 showed that 368 magnitude-4 or higher earthquakes occurred over the past year. That is more than double the number that occurred in 10 years before the 2011 disaster, when an annual average of 136 was recorded.

Seismic activity still remains high and impacts wide areas,” said Naoshi Hirata, head of the committee and professor of seismology at the University of Tokyo’s Earthquake Research Institute.

It is still more likely that earthquakes that can cause significant damage will occur. So be prepared and keep your guard up.”

According to the committee, 5,383 magnitude-4 or higher temblors occurred in the year immediately following the magnitude-9 Great East Japan Earthquake.

Although the frequency has decreased since then, between 245 and 368 quakes have occurred annually over the last three years.

Furthermore, magnitude-7 or higher major tremors have occurred once every year since 2011, except in 2015.

March 11 marks the sixth anniversary of the quake and the tsunami, which triggered a triple meltdown at the Fukushima No. 1 nuclear power plant.