Thirteen of the 25 accused have been arrested on charges of abetment of suicide of nine members of a family that had borrowed money from them in Maharashtra's Sangli district, an official said on Tuesday.
According to a preliminary probe, the accused used to "harass and humiliate" the members of the Vanmore family as they were unable to repay the loans they had taken, apparently forcing them to take the extreme step, he added.
Some of the arrested accused already have cases related to money lending against them, the official said.
Popat Vanmore (54), who worked as a teacher, his brother and veterinarian Dr Manik Vanmore (49), their 74-year-old mother, wives and four children were found dead at their houses in Mhaisal village of Sangli district on Monday, the police had said.
Suicide notes were found from the two houses, located 1.5 km apart from each other and over 350 km from the state capital Mumbai, they had said.
A preliminary probe suggested that the two brothers had borrowed heavily money from various people, the police said.
"The contents of the suicide notes indicate that the family had borrowed money heavily from some people and was finding it difficult to repay it," Sangli superintendent of police Dikshit Gedam told a press conference.
"As the family members were humiliated for it, they took the extreme step," he added.
Prima facie, it looks like the deceased had taken the loan for some business, the officer said.
"We have already registered a case against 25 people from whom the family had taken money. The family was harassed and humiliated by these people, who forced them to take the extreme step," he said.
Of the 25 accused, the police have so far arrested 13 under Indian Penal Code Sections 306 (abetment of suicide) and 341 (wrongful restraint) and the relevant provisions of the Maharashtra Money Lending (Regulation) Act and the Scheduled Caste and Scheduled Tribe (Prevention of Atrocities) Act, the SP said.
Some of the arrested accused already have cases related to money lending against them, he added.
Multiple teams have been formed to trace the other accused, the SP said.
Asked if all the deceased had consumed a poisonous substance together, the officer said a probe to ascertain what they had consumed and how was still on.
"The cause of the deaths is still reserved and what substance was used is under investigation," he said.
Asked if there was any superstition angle to the case, the SP said so far, the debt burden seems to be the prima facie reason behind the incident, but the police will look at all possible aspects.