Japanese utility Shikoku Electric Power Co said on Friday it had been ordered by a Hiroshima court to suspend operations of its only operable nuclear reactor, the No.3 unit at its Ikata plant in western Japan.

The reactor had been shut for regular maintenance work since late December and was likely to restart within a couple of months, but must now remain idled pending an appeal. Shares in the company, which didn’t disclose the court’s reason for issuing its order, plunged on the news, ending the day down 6%.

The move is the latest in a series of setbacks for an industry still struggling to recover from the Fukushima nuclear disaster nearly nine years ago, with less than a fifth of Japan’s reactors having received approvals to operate.

Residents around Japanese reactors have filed numerous lawsuits against nuclear operations in recent years leading to some temporary closes. Utilities have generally been successful in having rulings against them overturned on appeal.

In a statement, Shikoku Electric said the decision by the Hiroshima High Court is “extremely regrettable”, pledging to “promptly file an appeal so that the order can be revoked as soon as possible”.

It is the second time Shikoku Electric has received a court order to halt Ikata’s operations. In September 2018, Hiroshima High Court reversed a lower court’s decision that had forced it to be idled for about a year.