Japan’s recently established nuclear watchdog has apologized over a blunder in its forecast maps supposedly showing the spread of radioactive fallout.

The maps, released on Oct. 24 by the Nuclear Regulation Authority, projected the likely spread of radiation from a serious accident at 16 nuclear power plants but had indicated inaccurate wind directions and miscalculated distances, according to Hokuriku Electric Power Co.

Horuriku Electric pointed out the errors, involving six areas, to the Japan Nuclear Energy Safety Organization (JNES), which made the calculations, on Oct. 26, Asahi Shimbun reports.

“We are to blame for the very fact that an external body pointed out the errors,” NRA deputy secretary-general Hideka Morimoto told a news conference.

“The objective of the Nuclear Regulation Authority is to set up a system to supervise nuclear plant operators, but regretfully, we are not living up to the goal. We will learn from the experience for what we do in the future”.

NRA officials said the errors were a result of faulty coordination between different operators who use different coding systems but acknowledged that they should have verified the data.

Local government officials from one of the projected affected areas expressed frustration over the errors. “I want them to convey accurate information, because we have to draw up an evacuation plan by March,” Mito Deputy Mayor Mitsuru Tajiri said.