The 15-year-old girl was at the tea shop in Sangam Vihar run by her mother when Brijesh, who runs a retail store next to her shop, allegedly lured her over to his shop.
When the girl reached the shop, Brijesh allegedly downed the shutter and attacked the girl.
"She resisted but Brijesh allegedly beat her up and raped her. He later threatened her with dire consequences if she revealed the incident to anyone," a senior police official said.
The incident came to light when the girl returned home and narrated to her mother what had been done to her.
Police was informed and a medical examination confirmed that she was sexually assaulted.
Brijesh was arrested.
