A 16-year-old boy was stabbed to death in north-east Delhi’s Usmanpur by his former girlfriend’s brother and her new partner, police officers aware of the case said on Thursday after arresting the two assailants.

The murder took place on Tuesday night, police said, adding that the girl, 17, is absconding.

Giving details about the case, police said the boy lived with his family in a rented home in Usmanpur, and the girl and her family lived in the same building.

Joy Tirkey, deputy commissioner of police (north-east), said the boy and the girl had been in a relationship for about a year-and-a-half, when the boy was apprehended by Noida Police in November for a theft in that city. Upon his release, he learnt that the girl had broken up with him.

“He spent four months in an observation home for children in Noida and was released in March. On being released, he got to know that the girl had broken up with him and had become friends with an 18-year-old boy named Yamin,” said the DCP.

Tirkey said the boy then started pressuring the girl to get back with him, and started threatening Yamin to back off. At the same time, the officer said, the girl’s brother, 19, got involved as he didn’t approve of the 16-year-old.

“That is when Yamin and the girl’s brother decided to kill him,” said the DCP.

HT is withholding the name of the girl’s brother as his name would help identify the minor.

On Tuesday night, Yamin allegedly called the boy to sort out their issues. “The girl’s brother was already present at the spot where the boy and Yamin began taking a walk,” said the DCP.

As they walked, the DCP said, the two suspects found the right moment. “The girl’s brother began stabbing the boy while Yamin held him. Then then left him bleeding with stab wounds to his chest, neck and head and fled,” Tirkey said.