A man jumped in front of a moving train after axing to death two of his cousin's children and injuring two others in Rajasthan's Bundi district on Wednesday, police said.
An illicit relationship seemed to be the cause behind the killing and suicide, they said.
The incident occurred in the wee hours near Lakheri area in the district, some 200 km from Jaipur.
"During preliminary investigation, it has come up that Jawahari Lal, 50, was in a relationship with his cousin's wife. He barged into his cousin's house with an axe and attacked his four children sleeping in the courtyard. The children's parents were in a bedroom," a police officer told IANS.
After attacking the children, Lal left the house and ran towards the nearby railway tracks.
"Some villagers chased him and informed the police. However, he committed suicide by jumping in front of a train," the officer said.
Two children, Surendra, 15, and Rinku, 13, died on the spot, while two others, Sunita, 12, and Pintu, 9, are undergoing treatment at a hospital.
Their condition was stated to be critical, the officer said.
"It seems Lal thought the children were coming in the way of his relationship with his cousin's wife. We are recording the statements of the people concerned with the case," the officer said.