The accused hit his friend, a 16-year-old, 22 times and threw the body into a pit along the banks of the Yamuna and surrendered before the juvenile justice board, police said.
The teenager said he was inspired by a television show to commit the crime last week.
He called his friend for a party in a forested area near a power plant. After having a few drinks, he told his friend he will perform a magic trick and asked him to cover his face with a cloth and lie down, police said.
Police said the teenager was hit 22 times with a stone. The accused threw the body into a pit.
The victim's family lodged a complaint at the Jaitpur police station. The accused joined the youth's parents to look for him and misguided them. Later, he reached the juvenile justice board and surrendered. Subsequently, he was handed over to police.
Police said "the accused claimed that the victim used to him since childhood. He used to beat him up for petty reasons and humiliated him in front of friends".
A case of murder has been registered against the accused. The teenager and the victim stayed at a labour camp beside a power plant in Jaitpur area. Their parents worked as labourers at construction sites. The teenagers had dropped out of school and used to assist their parents at construction sites.