A record 2,172 minors aged under 18 years old were subjected to abuse in Japan last year, police data showed earlier this week, as the novel coronavirus pandemic made it difficult for welfare workers to intervene.

Police alerted child welfare centers nationwide of a total of 106,991 cases in which minors were suspected to have been abused in 2020, up 8,769 from the previous year and surpassing 100,000 for the first time since comparable data became available in 2004, according to the National Police Agency report released on Thursday.

By month, the number of children referred to child welfare centers jumped 21.1 percent from a year earlier in March last year, when most schools in Japan were closed to curb the spread of the virus.

The figure also rose 16.8 percent in April and 13.8 percent in May on year, as the nationwide state of emergency declared over the pandemic was in place.

Of the 2,172 child abuse victims, 61 died, up seven from the previous year. Of the total, 1,775 or more than 80 percent, were subjected to physical abuse, followed by 300 who were sexually abused, 53 who were verbally and psychologically abused, and 44 who suffered neglect.

Of the 61 dead, 21 children were involved in family murder-suicides, 11 were either killed or abandoned immediately after birth, 14 were murdered and eight were fatally assaulted, according to the report.

The police launched investigations into a record-high 2,133 child abuse cases last year, which targeted 2,182 suspects.

Of the alleged abusers, 1,558 or 71.4 percent were men -- 995 of them biological fathers and 300 stepfathers or adoptive fathers. Among 624 female suspects, 588 or 94.2 percent were biological mothers, and 14 were stepmothers or adoptive mothers, it showed.

Tetsuro Tsuzaki, director of the Association for the Prevention of Child Abuse & Neglect, said the pandemic had made it difficult for welfare officials to conduct home visits in suspected child abuse cases so they were less visible.

"The situation surrounding child abuse might worsen further as more families become isolated and face financial difficulties" due to the pandemic, said Tsuzaki, who formerly headed a child welfare center.

In principle, child welfare centers in Japan are required to check up on the safety of children within 48 hours of receiving a report of suspected abuse.

Since the spread of the virus, Japan has seen cases in which welfare workers failed to examine the condition of minors.

In August last year, 3-year-old Manato Suemasu died at his home in Fukuoka Prefecture, southwestern Japan, with his mother and stepfather later charged with fatally assaulting him.

The city of Nakama, where the family lived, did not send officials to their home for a check, citing the risk of infection.

A manpower shortage at child welfare centers has increased the workload of officials as the number of suspected abuse cases continues to rise in Japan.

"We have definitely been short of workers in the past couple of years. We have to deal with so many cases every day," said Hideki Nakayama, head of a Fukuoka prefectural child welfare center in Tagawa.

Japan's welfare ministry said in January that it plans to increase the number of child welfare workers to around 5,260 by the end of March next year, up around 2,000 from fiscal 2017, as part of efforts to prevent child abuse.

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