The other two accused have been identified as Shubham Mishra (19) and Gaurav (22), they said.
Rahul had been fired recently by the boy's father and wanted to exact revenge. He planned the abduction of his former employer's son after taking inspiration from Hollywood movies, police said.
Deputy Commissioner of Police (East) Omvir Singh said the police were informed about the incident on December 22.
The complainant, who is the owner of a computer hardware store in East Delhi's Mandawli area, told the police that his son was taken to a juice stall by Rahul. He left the child there and accompanied the boy's mother for some other work.
The child was rescued but the accused fled the spot, the officer said. Subsequently, all the three accused were held, he said.
Rahul is a graduate from the Delhi University's School Of Open Learning (SOL), while Gaurav is a first-year student, police added.
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