The incident occurred on the 97-hundred block of Seaview Avenue just before 11:45 a.m.
According to authorities, the teen girls were arguing, one ran away and an 18-year-old chased her into the store
As the girl hid in a room, the 18-year-old girl was banging on the door trying to get to her, police said.
She was holding a glass bottle under her arm and a metal pipe in her hand.
As she forcefully banged on the door with the metal pipe, the glass bottle apparently shattered and fragmented under her arm.
It appears the wound eventually killed her, officials said.
Detectives are interviewing the other teen girl, but no charges have been filed.
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