Four people were killed and nine others injured in a shooting at Apalachee High School in Winder, Georgia.

Officials have identified the people killed as students Mason Schermerhorn and Christian Angulo, and teachers Christina Irimie and Richard Aspinwall.

The 14-year-old suspect, Colt Gray, has been arrested and will be prosecuted as an adult.

Here’s what we know so far about the victims of the attack.

Schermerhorn was one of two 14-year-olds killed. Friends of his mother told the New York Times that he had recently started at Apalachee.

He was described as a cheerful man who enjoyed reading, playing video games and visiting Walt Disney World.

Schermerhorn had an “optimistic attitude about everything,” Doug Kilburn told the newspaper.

Louis Briscoe described the moment he heard from Schermerhorn’s mother that the boy had died: “No one should have to go through this kind of pain.”

Lisette Angulo identified herself as the older sister of the other 14-year-old shooting victim.

On a GoFundMe page to raise money for his funeral, she said her brother was “a really good kid and so sweet and so caring.” She added that the boy was “loved by so many,” and expressed her sadness at his loss.

Schoolmates remembered him as funny and with a “laid-back” demeanor, Fox 5 Atlanta reported. A friend who said the two had been close since high school said he was “in denial” after hearing about the fatal shooting.

Christina Irimie was one of two teachers killed in the shooting.

The 53-year-old is listed on Apalachee High School’s website as a math teacher.

Students described her as patient and caring, Fox 5 Atlanta reported.

A second math teacher, 39-year-old Richard Aspinwall, was also murdered.

He was also the school’s American football defensive coordinator, US media reported. He has received tributes from his sports colleagues.

Nearby Mountain View High School called Aspinwall its former teacher and coach and said its “thoughts and prayers” were with his family.

Brandon Gill, the football coach at nearby Buford High School, wrote on social media that Aspinwall was a “wonderful person” who “would do anything for anyone.” He was a “great husband, father, teacher and coach,” he added.

In addition to the four dead, eight students and a teacher were injured.

The teacher was identified by his daughter as David PhenixAccording to the school’s website, he plays a role in supporting the curriculum.

His daughter said he had undergone surgery after being shot in the hip and she felt “so, so lucky” that he survived.

Little is known about the eight injured children.

According to police, all those injured in the attack are expected to recover.