The newborn stolen from Patna Medical College and Hospital reunited with his parents on Wednesday, spending four days with strangers.

Police recovered the baby boy in the morning from an under-construction building in the Phulwarisharif area on the outskirts of the city. The wife, and the childless son and daughter-in-law of a constable were arrested for hatching the conspiracy of stealing the child. The cop, Arvind Kumar, got a clean chit from his boss, though.

The woman who vanished with the two-day-old child from the hospital on Saturday is still at large. The police suspect her to be a member of an infant-trafficking gang.

Kalavati Devi, the crestfallen mother of the recovered baby, was speechless for a few minutes after getting back her son in the morning. Tears trickling down her cheeks, she told The Telegraph: “It is a great relief. See, my smile and happiness are back. I have no words to thank the police for giving me back my son.”

Kalavati, a resident of Arwal, gave birth to her son at Patna Medical College and Hospital (PMCH) last Thursday. She was shifted to the ICU on Friday with the newborn. The next morning, the absconding woman identified as Meena, picked up the baby from Kalavati’s bed and walked out of the hospital without any challenge, exposing loopholes in the security at the state’s premier health hub.

Patna senior superintendent of police (SSP) Manu Maharaj told The Telegraph: “The constable’s arrested kin — wife Gayatri Devi, son Sonu and daughter-in-law Nisha Devi — desperately wanted a child. The police believe Gayatri hired Meena to steal a baby from the PMCH. She was instructed to lift a baby boy.”

He said: “The CCTV footage revealed that there were three newborns — two girls and a boy — in the PMCH ward when Kalavati’s son was stolen. Meena acted like a professional. She moved along the ward for sometime, picked up the child and walked out without any anxiety. Gayatri was waiting for her outside the hospital. The duo immediately rushed to a Police Lines quarters, where Gayatri stayed with her husband, son and daughter-in-law.”

The officer said: “A little while after Gayatri and Meena reached the Police Lines quarters, they left for Mahendia Sohta village in Jehanabad district with Sonu and Nisha. According to the statement of the arrested trio, the baby was kept in the village till Monday. On Tuesday, they returned to Patna and put up at an under-construction building in the Phulwarisharif area. Acting on a tip-off, the police recovered the child in small hours on Wednesday. The police acted cautiously as there was a chance of the infant being harmed.”

The officer said: “We are sniffing a huge racket behind the theft of the newborn and Meena’s arrest will answer a lot of questions. There can be more people involved.”

A private nursing home at Valmi in Phulwarisharif is under the scanner because Meena had allegedly approached it for a birth certificate of the baby stolen f.

Maharaj said Srinivas, the director of the nursing home, was being interrogated by the police.

Giving a clean chit to Gayatri’s husband, the SSP said: “The constable (Arvind Kumar) had no hand in the crime. He actually helped the police in recovering the infant.”

Arvind hails from Jehanabad district. He is posted at the police headquarters in Patna.