An earlier death toll said three teachers and three students had been killed – a figure that was revised down by Thailand’s Prime Minister Anutin Charnvirakul later Friday.

The school shared a heartfelt tribute on its website to the five staff members killed in the shooting, along with their portraits in black and white, saying their “goodness and virtue” and “spirit as a teacher will remain in our memories forever.”

They were named as deputy head teacher Kittipong Somrat; math teacher Prapaporn Konsila, Thai language teacher Nantchanatporn Nakplang; guidance teacher Tiwaporn Wanich; and secretary Saifon Sirikitchakajorn.

Nantchanatporn, previously a student at the school, was described as a “much-loved” teacher who dedicated her life “completely” to the school, according to local media reports. Just two days before the attack, Tiwaporn was recognized with a certificate as an outstanding teacher, Bangkok-based news outlet Khaosod English reported.

Anutin indicated that the attack could have been much worse if the suspected gunman had continued his attack, since he still had more than 30 rounds of ammunition remaining.

Regarding a possible motive, the prime minister said that the suspect had been experiencing stress related to his studies.

The boy’s father, who CNN is not naming until the authorities identify his son, later told CNN he had no idea why the boy carried out the attack and that he had a “good school result.” He told CNN his son is “guilty” but he doesn’t know why the boy allegedly carried the attack.

During the attack, terrified students huddled together under their desks, sobbing as gunshots rang out nearby, video filmed inside a classroom and verified by CNN showed. Further video showed students running out of the school as a staff member helped them evacuate.

An unnamed rescue worker told the Reuters news agency that “it was total chaos” when they arrived at the scene, where they administered first aid to students who had wounds to their back, chest, and arms.

Using what police said was his grandfather’s handgun, the suspect opened fire at the well-known secondary school of about 3,000 students, located on a busy highway in the Bang Kruai district of Nonthaburi province.

Anutin later told reporters that the gunman had died after he turned the weapon on himself. The suspect was previously in a critical condition after the shooting, with doctors providing emergency treatment.

Emergency worker Kiatikhun Verapongpradith described performing CPR on the wounded gunman.

“We rushed up and found that the perpetrator had shot himself in the right side of the head and collapsed,” he told Reuters. “As soon as we saw signs of life, we had the team bring a board to carry him to the hospital.” He was later confirmed dead.

An 18-year-old student told Reuters that he initially thought there were firecrackers going off. “Then it started getting more frequent, like ‘bang, bang, bang’ and then it went quiet at one point. And the shooting started again,” they said.

Another student said he first heard what he thought was someone shooting at birds during his English class. Shortly after, another child ran in to inform them of the shooting.land’s worst school shooting in years

The class immediately scrambled to barricade the room, pushing tables and chairs against the door and turning off the lights. Looking out of the classroom window, the student said he saw the shooter carrying a gun and walking to the building where his class was located.

Those inside the room crouched down on the floor in the darkness, waiting for help for 30 minutes. “Luckily, no one in our classroom was injured. The shooter only walked past our classroom,” he said, according to Khaosod English, a Bangkok-based news outlet.

Concerned parents rushed to the school as news of the shooting spread.

The son of CNN’s senior travel producer Karla Cripps attends the school but was overseas at the time of the shooting, which began at about 10 a.m. local time.

“My son called me from Japan in a panic, telling me that he’d heard there was a shooting at his school. The kids were told to lock down in their classrooms, and he obviously was very upset,” Cripps said from outside the school.

Cripps said there was a “really sad atmosphere” at the school as ambulances streamed in and out, and parents comforted their children.

“My son heard his friend’s brother is in the hospital right now. He’s among the injured… It’s been terrible for everyone.”

Prior to carrying out the attack, the suspect had searched for and viewed websites related to mass shootings, police said. Authorities have seized nine computers or electronic devices from the suspect’s residence as part of their investigation.

The UN children’s agency (UNICEF) said the young age of the suspect raises “difficult questions” for society as it called for better mental health services for children in the wake of the attack.

UNICEF suggested improving mental health services for children and “working to make all schools free of all forms of violence, including emotional and physical violence.”

A schoolgirl cries outside her school where deaths and injuries were reported after a shooting in Thailand's Nonthaburi province, Friday.

A schoolgirl cries outside her school where deaths and injuries were reported after a shooting in Thailand's Nonthaburi province,

Thailand’s Deputy Prime Minister Yodchanan Wongsawat said Friday a new mental health action plan to support teachers and students would be announced following the shooting.

Meanwhile, Thailand’s Ministry of Education pledged tighter security measures at schools.

The ministry promised a fresh review of security procedures in schools, particularly measures to prevent weapons and other dangerous items from being taken onto school premises.

It also announced financial compensation to the families of those who were killed and injured in the shooting, including 20,000 Thai Baht (USD $600) for each victim who lost their life, and 5,000 Thai Baht (USD $150) for each person who sustained injuries.

A photo provided to CNN by a police official in Bangkok shows a single handgun and multiple rounds of ammunition scattered on the floor inside the school.

Gun ownership in Thailand is high, compared with other countries in Southeast Asia. There were more than 10.3 million civilian-owned firearms in Thailand, or around 15 guns for every 100 people, according to 2017 data from the Switzerland-based Small Arms Survey (SAS).

Gun ownership is legal in Thailand with a license, although a person must fit certain criteria, including being at least 20 years old and not having a serious criminal record. (CNN)

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