Four out of five children in suffer from emotional distress, said on Wednesday, 15 years after Israel slapped a strict blockade on the occupied territory.
Israel imposed the measure in June 2007, as fighters of the Islamist took control of the densely populated enclave. Since then, both Israel and Egypt have continued to severely restrict the flow of people and materials to and from Gaza.
In a report called "Trapped", Britain-based Save the Children said the mental health of Gazan children has continued to deteriorate.
Since 2018, the number of those reporting symptoms of "depression, grief and fear," had risen from 55 percent to 80 percent, the report said.
Save the Children's director for the occupied Palestinian territories, Jason Lee said: "The children we spoke to for this report described living in a perpetual state of fear, worry, sadness and grief, waiting for the next round of violence to erupt, and feeling unable to sleep or concentrate.
"The physical evidence of their distress - bedwetting, loss of ability to speak or to complete basic tasks - is shocking and should serve as a wakeup call to the international community," he added.
of 2.1 million.
Around 800,000 young people who have "never known life without the blockade," live in the territory, Save the Children said.
to protect its citizens from Hamas - the ruling authority in the Strip. However, the group is blacklisted as a terrorist organisation by much of the west.
Israel has claiming that extreme violence is needed for its own self-defence. Most recently in May 2021, around 250 Gaza Palestinians were killed in Israeli attacks.
Over the past 12 months, Israel has granted more work permits for Gazans seeking better-paid jobs outside the strip. It has also relaxed some restrictions on the flow of goods in and out of the territory.
However, the blockade remains broadly unchanged, with Palestinians generally barred from leaving Gaza through the Erez crossing to Israel.
Gazans also face huge obstacles exiting through the Rafah crossing to .
In a statement marking the anniversary of the blockade, said "Israel, with Egypt's help, has turned Gaza into an open-air prison".
HRW's director for Israel and Palestine, Omar Shakir, told AFP: "Young people face the brunt of (the blockade) because they don't know of a Gaza before the closure.
"Their horizons are forcibly narrowed to a 40 by 11 kilometre (25 by seven mile) strip of land and that prevents them from the chance to interact and engage with the world," Shakir said.