India's Supreme Court has said the government must explain what it is doing to prevent "honour killings".
The court order came as it heard a petition which said the authorities had "failed to prevent killings of couples and individuals in the name of honour".
Over the weekend two more couples were murdered in suspected honour killings - one in the capital, Delhi, and another in neighbouring Haryana state.
At least 30 people have died in such killings in the past 18 months.
Activists say dozens of cases of intimidation and torture of young couples have been recorded in the same period.
'On the rise'
Taking note of the rise in "honour crimes", the Supreme Court demanded responses from the the federal government and state governments of Punjab, Haryana, Bihar, Uttar Pradesh, Rajasthan, Jharkhand, Himachal Pradesh and Madhya Pradesh.
The court said it wanted them to explain what steps they had taken to protect young couples who are being threatened by their families and communities.
In a petition filed in the court, Delhi-based non-governmental organisation Shakti Vahini says cases of "honour killings" have been on the rise in India but the authorities have "remained mute spectators".
The group has been researching cases of "honour killings" in Haryana and western Uttar Pradesh for the past year.
It is now calling for a stringent law against "honour killings".
Most victims are believed to have brought "dishonour" upon the family, clan or community by marrying outside of the rigid caste system.
Over the weekend, two more cases of suspected "honour killings" were reported.
In Delhi's Ashok Vihar area, Kuldeep (26) and his wife Monica (23) were found murdered. Police said the couple married four years ago despite objections from their families.
In the village of Nimiliwali in Haryana, two teenage lovers were found dead in the house of the girl's uncle. Police said Monika (18) and Rinku (19) were tortured before they were killed.
They said they were looking for Monika's father, brother, uncle and cousins who were suspected to be behind the crime.
Last week, a teenage girl and her boyfriend were murdered in Delhi's Swaroop Nagar area.
Asha Saini and Yogesh Kumar, both 19, were beaten with metal rods and then electrocuted, police said. The girl's parents, uncle, aunt and a cousin have been arrested in connection with the murders.
In April, five Haryana men were sentenced to death and one jailed for life over the 2007 murder of a young couple, Manoj and Babli.
Village elders said they had violated local customs by marrying within the same sub-caste.