An enraged father threw his four-year-old son before a speeding bus near here, crushing the boy under the wheels.
News reports said Friday 35-year-old Mantu Sardar of Duttabad in North 24 Parganas district near here was on his way to a wedding of his second wife's relative with son Suman from his first marriage when he committed the crime in a fit of rage at Basirhat.
Police said Mantu's first wife died four years ago. He married Sabita later but their relationship soured soon after as Mantu accused Sabita of neglecting her stepson Suman.
Mantu also suspected his second wife of infidelity.
On the fateful day the three - Mantu, Sabita and Suman - had left home around 7 a.m. and took a bus to Basirhat, about 70 km from Kolkata.
"They kept quarrelling all the way to Kanmari Bazar. Even when they got off the bus around 9 a.m., they were squabbling. Suman was in his father's arms. Suddenly, Mantu became agitated and hurled Suman in front of a speeding bus that crushed the child under its wheels," police said quoting an eyewitness.
The driver tried his best to save the child by slamming the brakes but failed.
Angry residents began beating up Mantu. Police later rescued him and took him to hospital.
"We have arrested Mantu and will produce him in court," said North 24-Parganas superintendent of police Praveen Kumar.
Sabita was also taken to the police station but was not arrested.