Detectives are investigating whether the four men, three women and four girls could have been victims of feuding gangs.
The bodies were discovered by a neighbour early on Sunday morning in the northern Burari district of the Indian capital, which recently witnessed a deadly shoot-out between rival groups.
The body of a 70-year-old woman was found lying on the floor of the house, with the others hanging from a railing attached to the ceiling.
Last month, three people were killed and five were injured when members of rival gangs opened fired on each other in the main Burari market.
Police said the quarrel between the two groups dates back to 2013.