Mumbai: Karnit Shah, a six-year-old boy, who had gone missing from Mumbai on April 6 was traced to Handia in Uttar Pradesh's Allahabad district late on Tuesday and four people arrested for abducting him.The main accused is Sohan Singh, who runs a cake shop in Mumbai's Kandivali close to where Karnit stayed. Singh’s three associates - Sameer Khan, Sandeep Warige, Shankar Salve – have also been arrested.A Mumbai police team went to Lucknow to bring Karnit home. The boy arrived in Mumbai on Wednesday evening and was reunited with his family.There were scenes of joy, relief and celebrations at Mumbai airport as Karnit was returned to his parents.Mumbai Police Commissioner Arup Patnaik said that raids were carried out at five-six places with the help of local informers to trace Karnit and his abducters."The main accused came to know of the raids as his local associates were picked up. Uttar Pradesh Special Task Force and Uttar Pradesh local police extended tremendous help to our team who had gone to Kanpur to trace the boy," said Patnaik while addressing a press conference after Karnit reached Mumbai.Karnit was kidnapped from within his apartment complex allegedly by a worker employed at a bakery near his residence. While Mumbaikars responded to the family's pleas, there was no breakthrough until Sunday when information came in that the boy had been taken to Kanpur via Nashik and Allahabad to extort a ransom of Rs 1 crore. An overwhelmed father had nothing but thanks for everyone.Karnit's uncle Devang Mehta had turned citizen journalist to help find the boy. Besides seeking police help, Mehta actively used the social media network to reach out to the masses, hoping that young Karnit would be found soon.On April 6, Karnit, a resident of Mumbai suburb, was playing with his friends in the building compound where he lived after which he didn't return home.Karnit's photograph was uploaded on Facebook on April 9 and since then online communities picked up the message and spread the word around.With four of the accused in police custody, the case will now be further investigated before charges are filed. 6-year-old Karnit is now smiling again, with a special gift from the Mumbai Police also thrown in.