When police arrived at Jonathan Law High School in Milford, USA to respond to a report of an altercation in April 2014, they found "considerable blood evidence" at a stairwell and recovered a knife in a hallway, not far from the grisly scene.
The victim of the fatal stabbing was a 16-year-old girl, Maren Sanchez, who was later remembered as outgoing and kind, the type of girl who "brought people together."
The suspect was a teenage boy, Christopher Plaskon, whose hands and clothes were covered in blood in the aftermath, according to a probable cause statement.
"I did it," Plaskon told a school resource officer, according to the police document. "Just arrest me."
The reason for the attack, authorities would later say: Sanchez had turned down Plaskon's invitation to the school's junior prom, a dance that had been scheduled to take place that day.
Sanchez died of stab wounds to her neck and trunk, according to the county medical examiner. Plakson was charged with murder.
"Maren should be celebrating at her prom this evening with her friends and classmates," Sanchez's cousin, Edward Kovac, said after her death, according to the New Haven Register.
"Instead, we are mourning her death and we are trying to understand this senseless loss of life."
On Monday, Plaskon accepted a plea deal in the case, the Associated Press reported. The 18-year old, who pleaded no contest to a murder charge, will be sentenced in June, according to AP.
Documents obtained by the Hartford Courtant in December indicated that Plaskon's father, David, told investigators that his teenage son "had recently appeared to be bothered by the fact he was turned down by a female to attend the high school prom."
The teen had said he "wouldn't mind if [Sanchez] was dead or hit by a bus," a friend told authorities, according to the newspaper's report.
David Plaskon didn't notice any red flags in his son's behavior the day of the attack, he told police.
He said his son seemed to be "in good spirits" when he arrived at school that morning, according to the Courant, which cited the documents.
Reports the newspaper:
"David and his wife, Kathy Plaskon, told police that their son had a significant history dealing with mental health issues as a child, and that he had received treatment for behavioral issues such as mood swings, depression, suicidal tendencies and self-mutilating behavior, the documents say."
A message left for Plaskon's attorney was not immediately returned Monday.
Sanchez was supposed to graduate last June and was remembered at her the Class of 2015's graduation ceremony, where she received a posthumous diploma, the Milford Mirror reported.
Students released purple balloons when her name was called, as onlookers stood and clapped.