SHIJIAZHUANG - Twenty-one individuals, including the operators of the nursing home, have been transferred to judicial authorities for criminal investigation after a fire there killed 20 people in April this year.

The fire broke out on April 8 at a nursing home in Longhua county, Chengde in North China's Hebei province, where 39 elderly residents were living at the time.

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According to a report released by provincial fire rescue authorities on Tuesday, the blaze was caused by a short circuit of a power board at the facility. The emergency situation was spotted too late, the corridors were not sufficiently insulated and the automatic sprinkler system partially failed, leading to high casualties, the report said.

The report ascertained the nursing home's failure to fulfill its fire prevention responsibilities. It also points out problems including the illegal use of substandard power boards and the unlawful renovation at the facility.

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A total of 45 public officials are under investigation for their accountability, the report said.