An 18-year old city girl was allegedly killed by her brother in the name of “honour” after she got married to a boy of another caste.The victim, Manjit Kaur (18), who belonged to the Sainsi community, was working as a domestic help in New Officers Colony. She got married a few days ago, but told her mother about it yesterday. “Her brother Bhaironath was upset when he learnt about the marriage,” the police said.Last night, when the mother and daughter were sleeping on the first floor of the house, someone entered the room and attacked Manjit Kaur with a sharp weapon killing her on the spot.“We suspect that Bhaironath attacked her sister in a fit of rage as he was against her getting married outside the community. He had warned her of dire consequences a few hours before the crime and had threatened to eliminate her if she did not end her relationship with her husband,” said Jaswinder Tiwana, SHO, Civil Lines.