The teenager's body was recovered two days ago from a house, with throat slit and body tied to a chair, they said.
"During the investigation, it was found that the teenager was killed by his juvenile friend, with whom he used to consume ganja," a senior police officer said.
Teams were deployed and the accused were apprehended yesterday.
During interrogation, the juveniles said that the teenaged boy used to harass the sister of one of the accused and had been warned against pursuing her girl, but he persisted.