Japanese Industry Minister Banri Kaieda apologized over reports that he threatened to ‘‘punish’’ firefighters if they did not work at the quake-hit nuclear plant in Fukushima Prefecture.

The apology came after Tokyo Governor Shintaro Ishihara protested to Prime Minister Naoto Kan over the ‘‘forcing’’ of Tokyo Fire Department to engage in an hours-long water-spraying mission, saying they were threatened with ‘‘punishment’’ if they refused.