Arham Hussain, a Class 8 student, who had gone to a saloon for getting his hair cut on Friday, did not return home. His parents, who deal in construction material, then informed the police.
During investigation, police suspected the saloon as it was shut today despite being Sunday when many customers visit the saloon, a senior police officer said.
The gate of the saloon was broken open, and the inside scanned. Arham's body was found in a steel box in a decomposed state, the officer said.
The officer also said that Arham's parents had received a ransom call yesterday, demanding Rs 10 lakh for his safe release.
The parents had also pasted posters and hoardings at several places seeking information about their son.
"Police have registered a case under appropriate section of the IPC at Jamia Nagar police station and further investigation is on," the officer said.