Police in India's capital said they found 11 bodies in a home under mysterious circumstances on Sunday, including 10 that were blindfolded and hanging.
The victims were all from the same family and most had lived in the home where they were found in Burari village in the northern part of New Delhi, said police officer Vineet Kumar.
Kumar said police began their investigation after they received a call Sunday morning that some "members of a family have committed suicide."
But he said that no suicide note was found, and that police were investigating whether the victims — four men, three women and four girls — died by suicide or were killed.
There were no bullet marks on the victims' bodies and there was no sign of forced entry into the house, Kumar said. "We're yet to reach any conclusion whatsoever," he said.
Ten bodies, blindfolded by cotton and pieces of cloth, were found hanging from an iron grill used as a ventilator in the home's courtyard, while the body of a 70-year-old woman was lying on the floor of the house, said a police official who spoke on condition of anonymity, in line with department policy.
The family had lived in the house for more than two decades, the Hindustan Times newspaper reported. It said the house belongs to a businessman who ran a plywood shop and dairy.
According to media reports, the family migrated to the capital from the northwestern state of Rajasthan about two decades ago and police were trying to get in touch with relatives there.
The newspaper said that at around 8 a.m. Sunday, a neighbor with whom the businessman used to go for morning walks went to see him and found the door of the house open and the 10 people, including the businessman, hanging. He raised an alarm and people called the police.
A police statement said some handwritten notes were found in the house "which point towards observance of some definite spiritual/mystical practices by the whole family".
"These notes have strong similarity with the manner in which the mouths, eyes etc of the deceased were tied and taped."
This angle was being investigated and a case of murder registered, the statement said.
The home of those who died is above a grocery store the family owned in the Burari district in a northern part of Delhi.
It is near to where three people were killed and several injured in a shootout between two gangs just two weeks ago, but police said there was no apparent link.
Arjun Thukral, a relative of the family who lives in the same neighborhood, said he ran to the victims' house as news of the deaths spread.
"I saw the bodies hanging, stools lying around, and my wife's aunt sprawled on the floor by the bed. I couldn't bear watching anymore," he said.
Thukral questioned whether the family had died by suicide.
"No father can kill his own son. ... How would a mother be able to kill her own children? I don't think they committed suicide. These are murders," he said.
New Delhi Chief Minister Arvind Kejriwal, who visited the scene, called the incident "tragic."
"Police are investigating. ... Let's wait for their investigation to be over," he said.
In a video posted on Twitter by Kejriwal's ruling party, the neighbors are heard telling Kejriwal that the family was busy with wedding preparations.
A neighbor of the family said they couldn't have died by suicide, New Delhi Television reported. The neighbor said he spoke to one of the victims Saturday night and found no sign of any stress, the report said.
Indian TV channels broadcast interviews with neighbors who said the family did not have any discord among themselves.Police official Rajesh Khurana told reporters that all angles were being investigated. "We can't rule out anything," he said.