In a suspected case of 'honour killing', a 17-year-old college-going girl was killed by her parents and grandmother in Adilabad district of Telangana on Friday as they feared that she would elope with a youth from another caste, police said.

The incident took place at Neradigonda village.

Lakshman Singh strangled his daughter to death with the help of his wife Chandrakala and mother Panchavati at about 3:30 am on Friday, inspector K Nagendra Chary said.

The girl had asked her lover who is from another caste to come to the house. When the youth went to her house on Thursday night, Singh had a heated exchange with him.

"Afterwards Lakshman, his wife and his mother decided to kill the girl and used a dupatta to strangle her," the police officer said. 

Lakshman has two more daughters, Chary said. 

The three accused had been detained and probe is on, he added.