A 12-year-old girl who sustained critical wounds at a school shooting outside Bangkok on Friday has died, officials said Saturday, bringing the death toll from the attack to at least six people.

A 14-year-old opened fire at Debsirin Nonthaburi School in Nonthaburi province northwest of the Thai capital around 10 a.m. on Friday before taking his own life, officials said. He also appeared to have killed his two grandparents at his family home earlier in the morning.

Five school staff members, including teachers and administrators, died in the shooting.

The girl, 12, died after hospitalization, the Health Ministry said. The school had posted a message on Facebook Friday seeking blood donations for two students, including the girl, who was in seventh grade.

Bangyai Hospital, about 3 miles from the school, said 23 people were wounded, of whom 10 were in critical condition, with most suffering gunshot wounds. Earlier reports gave conflicting casualty numbers.

Fourteen people remain hospitalized, of whom seven remain in critical condition Saturday, according to Thailand’s Health Ministry. Most of those wounded were between 12 and 14 years old.

Relatives claimed the bodies of eight people from Bangkok’s Institute of Forensic Medicine: five school staff, the accused shooter, and his grandparents. Emergency workers brought out a coffin and loaded it onto an ambulance, which will transport the bodies to their hometowns for funeral rites.

The young girl’s body is still to be released.

Wiroon Supasingsiripreecha, head of the institute, said most of the victims suffered a single fatal gunshot wound to a vital area, including the chest or head.

He said the gunshot wound found on the alleged shooter was consistent with the weapon he had used. More detailed forensic findings, including toxicology results, are expected later, he said.

Officials said the gun, described as small and compact, was legally registered to the boy’s grandfather.

There were reports that the boy, who lived with his grandparents, had shown signs of school-related stress, although some of his relatives told Thai media they were unaware of any troubles he might have been facing.

A witness said students hid inside a classroom while they heard gunshots from another building before police officers knocked on the door and cleared a way for them to leave the building.

Amporn Niamfuang, who owns a restaurant 160 feet from the school, said there was the sound of a single gunshot and then a pause.

“And then there were multiple continuous shots,” Amporn said, recalling the narrow road outside the restaurant filling with fleeing students. “Students were running scared and pouring onto the street. Young girls were holding each other’s hands and crying. I went inside to hide.”

The co-educational state school, which has about 3,000 students enrolled aged 12 to 18, said all classes would be suspended between Aug. 10-14 and school staff were instructed to work from home during that time.

A few mourners laid flowers Saturday morning at the school’s gate, where police officers could be seen.

Charin Siriananchai brought his two sons, ages 9 and 6, to pay their respects. He said while his sons do not study here, he lives in the neighborhood and drives past this school almost every day, often stopping to allow students to cross the road.

“Everyone was saddened and shocked, because it was unexpected that this would happen in Thailand, and also it’s quite a great loss,” he said.

Some parents also came with their children to collect their belongings left behind after the shooting. A father, who declined to identify himself, said his son, who was at the school during the shooting, was still in shock and could not sleep alone.

Thailand has one of the highest rates of gun ownership in Asia, second only to Pakistan and far surpassing its Southeast Asian neighbors.

Data collected in 2017 by the groups Small Arms Survey and GunPolicy.org in their last extensive international study found civilian gun ownership in Thailand was about 15.1 guns per 100 people, compared with less than one per 100 in neighboring Malaysia.

Thailand had 3.49 deaths by firearms per 100,000 people, according to 2023 statistics published by World Population Review. That puts it well behind parts of Latin America and the Caribbean, but relatively high in Asia. Only the Philippines is higher in Southeast Asia.