Youth suicides by firearms in the United States are at their highest rate in more than 20 years as the number of children, teens and young adults who have taken their lives with guns increased more than in any other age range, a report said Thursday.

The report by Everytown For Gun Safety — a nonprofit that advocates for gun control — found that from 2019 to 2020, the rate of firearm suicides during the COVID-19 pandemic increased by 2 percent as a whole, but the rate among children ages 10 to 24 increased by 15 percent.

The firearm suicide rate between the ages of 10 and 14 increased by 31 percent from 2019 to 2020 — the highest reported rate for that age group by the Centers for Disease Control and Prevention since 1968. Over a longer period, from 2011 to 2020, the rate increased by 146 percent, researchers for Everytown found.

Research by the CDC's Adolescent Behaviors and Experiences Survey found in 2021 that at least 1 in 5 high school students had seriously contemplated suicide and nearly 1 in 10 had attempted suicide in the past year.

Boys and young men represent nearly 9 out of 10 firearm suicide victims, Everytown found. They also are seven times more likely to kill themselves with a gun compared with their female peers, according to the CDC.

Youth who identify as Native American or Alaska Native are more than 1.5 times more likely to die by firearm suicide, followed by white and black youth. Firearm suicide rates across all racial and ethnic groups have increased dramatically over the past decade.

While young Asians and Pacific Islanders (APIs) have the lowest overall rate of firearm suicide, they have seen the steepest increase of firearm suicide rate over the past decade, at 168 percent, the report showed.

Among Hispanic youths, there was a 128 percent rise, while the rate among black youths rose 115 percent.

Racial and ethnic minority groups in the US are among those hit hardest by the increased suicide rate, Everytown research director Sarah Burd-Sharps told ABC News. A lack of access to mental health care resulting in higher rates of untreated depression as well as traumatic exposure to discrimination and racism are among the driving factors, she said.

"The research shows pretty clearly that people who struggle with mental illness are much more likely to be victims than perpetrators of violent crimes," she said.

The report noted that experts haven't determined exactly what is causing more young people to turn to suicide with guns, but it attributed the suicide risk of the age group to a combination of three main factors: life stressors, historical risk factors and access to lethal means of harm.

In the wake of two mass shootings by two teenage gunmen — an 18-year-old in Buffalo, New York, and an 18-year-old in Uvalde, Texas, last month — the report recommends expanding "red flag" laws.

"Research shows they save lives," Burd-Sharps said. "They very much prevent youth suicide."

Red flag laws temporarily prevent anyone, particularly the young, from being able to own a firearm if they show signs of mental strain or worrying behavior that could cause them to harm themselves or others. At least 19 states have red flag laws.

Professor David Studdert, an expert in health law at Stanford Law School in California, told China Daily: "Red flag laws are a promising strategy; these laws allow family and friends who are worried about their loved ones' mental health to petition for removal of guns."

So far, 19 states have passed such laws that allow local authorities and family members to petition in civil court for the restriction of a person's firearm access, according to Everytown.

Overall, acts of suicide are fatal in 8.5 percent of cases, while acts of suicide involving a firearm are fatal 90 percent of the time, according to a 2019 study published in the Annals of Internal Medicine.

Suicides have long been a driver of firearm-related deaths in the US. More than half of all gun deaths in 2020 were suicides, according to a 2022 Pew Research Center report.