Kansai Electric Power Co. said Wednesday it would suspend operations at two nuclear reactors after missing a deadline set by the industry regulator to build counterterrorism facilities.

Under stricter rules implemented after the 2011 Fukushima disaster, utilities are now required to build emergency off-site control rooms to serve as backup bases that can keep nuclear reactors cooled and prevent meltdowns in the event of a terrorist attack.

The suspension of reactors Nos. 3 and 4 at Kansai Electric's Takahama plant in Fukui Prefecture — for about five months from August and four months from October, respectively — will be the second time for reactors to be shut down in Japan because such off-site facilities were not ready. The No. 3 reactor at the plant will be shut down from August 2 to Dec. 22, and No. 4 will be offline from Oct. 7 to Feb. 10, 2021.