Violence against children in the Pacific region has reached “endemic” levels, with children subject to brutal physical discipline in the home, as well as sexual violence, a new report has found.

More than 4 million children across the region had experienced violent discipline in the home and in Papua New Guinea 27% of parents or caregivers used physical punishment “over and over as hard as they could”, the report by leading NGOs working in the region found.

“The levels of physical, sexual and emotional violence in the region are shockingly high and it is something that we all need to come together to work around because that level of scale of violence is going to have long-term detrimental impacts for children,” said Kavitha Suthanthiraraj from Save the Children Australia, the author of the Unseen, Unsafe report, which was published on Tuesday.

“It’s not talking about the normal kind of disciplining tactics that people might use, it’s more heavy-handed physical and/or humiliating punishment,” said Suthanthiraraj.

The report also found that 24% of adolescent girls (aged 15-19) in the countries surveyed had experienced physical violence and 10.5% had experienced sexual violence.

In Papua New Guinea, rates of sexual violence against children are “exceptionally high”, the report said, with Médecins Sans Frontières reporting that children were the victims in more than 50% of sexual violence cases referred to their clinics in the regions of Port Moresby and Tari.

“While the drivers of violence in the region are complex and inter-generational, targeted programs are making a difference,” said Suthanthiraraj, with the reporting highlighting a “dramatic underinvestment” from Australia and other aid donors in the region in tackling violence against children.

In 2017, Australia spent just $1.1m on programs specifically targeted at ending violence against children in the Pacific and Timor-Leste, just 0.1% of its spending on overseas development assistance for the countries.

Suthanthiraraj said that, given the Australian government announced a “step-up” in the Pacific region last year and committed to spending $2bn on an infrastructure financing facility, a suggested increase in violence program funding from 0.1% to 1.5% was “tiny” in comparison.

Tackling the problem required a “holistic approach”, Suthanthiraraj said, including education programs to teach children what behaviour is inappropriate and where to turn if they feel unsafe, and positive parenting programs to teach other methods of discipline, which she said “get really good responses in the community”.

While “endemic issues” such as gender inequality and some beliefs in some communities about the rights of children, posed difficulties, it was incredibly important to tackle the problem when children were young, because research suggests that perpetrators of family violence are likely to have been the victims of it when young. “Some of the research we’re finding is if we don’t tackle it when they’re young , it’s just going to perpetuate when they get older,” she said.

Another report published today by the International Finance Corporation explored the cost on businesses of violence against women. Pacific countries have some of the highest rates of violence against women and girls in the world, with almost two-thirds of women experiencing domestic or sexual violence in their lifetimes. In Kiribati, 68% of women experienced intimate partner violence in their lifetimes, according to the report.