The incident took place six months ago in the elevator of a residential building in the Möllevången of Malmö, reports the Sydsvenskan newspaper.
The two 15-year-old’s lured the younger girl into the elevator in order to exact revenge for demeaning messages posted by the 13-year-old via the MSN internet chat website.
“Why have you been so tough on the screen and called me things?” asked one of the 15-year-olds before the start of the assault, according to Sydsvenskan.
The two older girls then knocked the 13-year-old to the ground and began to kick her repeatedly in the head and torso.
They also pressed lit cigarettes into the younger girl’s chest and hands while at the same time calling other friends to come and witness the revenge attack.
A total of nine young people eventually arrived on the scene, and at one point the 15-year-olds forced the 13-year-old girl to lick the shoes of one of the boys standing in the group.
The beating continued for nearly four hours, and before leaving the scene, one of the 15-year-old’s threatened the younger girl with a pistol.
The 13-year-old spent four days in the hospital following the beating. Six months on, her nose remains swollen and she continues to have trouble breathing, the newspaper reports.
In delivering its guilty verdict on Wednesday, the Malmö District Court characterized the 15-year-old’s attack of the 13-year-old as “raw”, “drawn out”, “torture-like”, and “deeply degrading”.
The two teenagers were convicted of aggravated assault, obstructing justice, as well as for making illegal threats and were sentenced to juvenile rehabilitation and community service. They were also ordered to pay 21,000 kronor ($2,640) in damages.
The court added that, had the two teens been adults, the severity of their crimes would have likely resulted in two-year prison sentences for them both.