A husband-wife duo in their late twenties chose the noose over their baby girl and hanged to death in front of her at their Chas home, 1.5km from Bokaro steel city, on Wednesday night.

Police are clueless about the reason behind the bizarre suicide pact of the well-to-do couple.

Son of a late Bokaro Steel employee, Pradip Kumar Mahto (29) had tied the knot with his second wife Kalyani Devi (26) three years ago after an eight-month marriage that ended in divorce.

On Wednesday evening, the two were alone at home with their 18-month-old daughter, while one of Pradip's unmarried sisters was visiting a relative. They spoke to neighbours till 8pm and called it a day soon thereafter.

Police said around 10pm, relentless wails of the baby woke up neighbours. When they came to enquire what the matter was, no one answered the door. They peaked through the window and saw Pradip and Kalyani hanging with ropes from the fan. The little girl sat on the floor crying.

The door was forced open and Chas police informed around 11pm.

On what might have prompted the twin suicides, Bokaro SP Kuldip Dwivedi said the matter was under investigation and confirmed that the couple had not left behind any note. "The bodies have been sent for post-mortem and neighbours are being interrogated," he added.

Some neighbours said Pradip had received Rs 20 lakh as death benefits from the steel plant management after his father R.K. Mahto died in an accident last year. The couple also owned two ancestral houses and several acres of land in Chas block. So, money crunch behind their suicide could be safely ruled out.