A 13-year-old girl slashed a schoolgirl's face with a razor blade, a court has heard.
Pictures of the teenager's injuries were shown to the jury
Sheffield Crown Court was told Shanni Naylor, now 13, needed 30 stitches in her face following the attack at a Sheffield school in 2005.
The prosecution said the girl walked to the back of the classroom where Shanni was being helped by a teacher.
The girl, who was 12 at the time of the attack, denies wounding with intent to cause grievous bodily harm.
The jury heard Shanni describe in a video recorded police interview how she was in English class when the girl, who cannot be named for legal reasons, approached her and began slashing her across the face without warning.
She said the defendant swore at her and said: "I hate you", before launching her attack.
Shanni said: "I was scared and mad because she just attacked me and left me scarred and I saw blood coming down my face and on to my jumper."
Under cross-examination, Shanni was asked about a fight she had with the defendant the day before the incident.
Jeremy Baker QC, defending, said to Shanni: "I suggest you did attack her and you attacked her quite badly the day before."
Shanni replied: "No."
A school teacher later told the court the defendant had been subjected to bullying, but said she had not witnessed these incidents herself.
The teacher said there had been a lot of talk in the school about the link between the incident involving the blade and the fight the day before.
She said: "Some staff thought the incident on the 19th could have been avoided had there been a suspension after the fight."
The court has heard there is no dispute that the defendant attacked Shanni and caused her injuries. The only issue in the case is the youngster's intent.
The trial continues.