On the intervening night of March 4 and 5, Dilawar along with the four accused - Aditya, Rihan, Monu and Ravi - consumed liquor at Bhopura road trisection and then went to a brick kiln in Sikanderpur village area in an auto, Assistant Superintendent of Police Vipin Tada said.
At the brick kiln, Aditya and Rihan indulged in unnatural sex with the victim. But when Ravi and Monu tried to force themselves on Dilawar, he protested following which they had an heated exchange, he added.
All four accused were arrested from Garima Garden under police station Sahibabad, Tada said, adding, the pistol used for the murder, Dilawar's mobile phone and the auto have been seized from them.
Dilawar's post-mortem report has confirmed unnatural sex.
A case against the accused has been registered under relevant sections of the IPC, police said.