A relative outside trader Sanjay Singh’s Behala home. Picture by Pradip Sanyal

Sanjay Singh, a 43-year-old trader who went missing from his Behala home on Sunday night, returned on Monday evening under mysterious circumstances.

Singh’s family members received several calls during the period, one of them from the trader, who said around 2pm on Monday that he was in Madhyamgram and would be returning home soon.

The relatives refused to divulge the details of the other calls. They lodged a missing complaint with Behala police station early on Monday.

Police are investigating whether the trader was kidnapped and whether he returned home after payment of ransom.

Sanjay’s brother-in-law Ramakar Singh said around 11.45pm on Sunday, three men and a woman arrived in Pathakpara in a taxi and asked the residents to point out the trader’s house. “When Sanjay answered the doorbell, they asked him to accompany them. They got into an Alto which sped away.”

Sanjay’s parents, wife, three daughters and a son tried to call him on his cellphone several times but could not get through. He contacted them on Monday afternoon and returned in a taxi around 7pm.

South 24-Parganas police superintendent Praveen Kumar said several members of the family had received calls regarding Sanjay’s disappearance but refused to divulge the details.