, Nova said that unpaid salaries would be paid and that students would receive refunds by the end of the month. Now, they file for bankruptcy protection. We can't trust what Nova officials say," said Katsuji Yamahara, a union representative.

Toshiaki Higashibata, a lawyer representing Nova, told a separate news conference that unpaid salaries had reached ¥4 billion. However, Yamahara warned that the government needed to ensure Nova provides proper documentation of unpaid salaries in the weeks and months ahead.

"We're worried that even if the company undergoes restructuring, the same problems related to unpaid salaries will not be solved. Nova should continue paying teachers and staff, even though the schools are now closed down," Yamahara said.

The concern about receiving unpaid wages is especially strong among employees and union officials because Nozomu Sahashi, who was ousted as Nova president Thursday, has disappeared and it remains unclear as to who is in charge.