The judge also imposed a fine of Rs 50,000 on the accused Chetan Das, Government council Rajendra Kasana said.
ADJ Mangal Prasad however released Chetan's wife Meenu due to lack of evidence against her.
Prem Nagar resident Chetan Das had lost money to one Prem Kumar in a gambling session and to avenge this Das kidnapped Kumar's 13-year-old son Lalit.
After his son went missing, Kumar had filed a complaint against Chetan and his wife following which they were arrested.