Allahabad High Court on Monday acquitted businessman Moninder Singh Pandher and his domestic help Surendra Koli in the serial murders of 19 girls and young adult women in Nithari, citing inconclusive evidence and suggesting a “botched” CBI investigation.

Death-row convicts Pandher, 70, and Koli, 55, have been in jail for over 16 years since their arrests in December 2006 and January 2007, respectively, following the discovery of bones, skulls and body parts from a drain outside Pandher’s bungalow in Nithari, Noida.

Pandher has been acquitted in the two remaining cases out of six in which he had been convicted and sentenced to death by CBI courts. A sessions court and the high court had earlier acquitted him in four cases.

Koli, acquitted on Monday in 12 cases in which he had been sentenced to death, is undergoing a life term in a 13th Nithari case where the high court had commuted his death sentence in an earlier verdict. The government has challenged this relief in the Supreme Court, where it is currently pending.

There was no word from the government on whether it would challenge Monday’s acquittals, but the victims’ families — poor working-class members from Nithari — expressed anguish at the verdict and stoned Pandher’s empty house in frustration.

Many of them said the CBI had deliberately messed up the case to help the “rich businessman” Pandher. “The investigators behaved as though they were Pandher’s servants. They would scold us while asking questions but speak softly to Pandher and Koli,” a victim’s mother said.

PTI said the high court expressed “disappointment” at the probe, saying the prosecution had “botched up” the probe, “brazenly violated” the basic norms of evidence collection and kept changing its stand.

Pandher and Koli had been accused of luring poor girls from nearby hamlets to Pandher’s bungalow, raping them, chopping them up and throwing the pieces into a drain. Local people had alleged cannibalism too.

The prosecution had claimed that defendant “SK” had given “detailed, graphic and highly repetitive account(s) of how he lured, attempted to rape, killed, dismembered, ate each of his victims and how he disposed of their bodies”.

But the bench of Justice Ashwani Kumar Mishra and Justice Syed Aftab Husain Rizvi noted that “SK” had later alleged “he has been extensively tutored by them and made to memorise parts of his confession pertaining to the names of the victims, the dates and times of their killings, the manner of their killing, etc”.