Fiji police were investigating after a crying baby and the bodies of five family members were found this week on the side of a cliff.
The victims may have been poisoned, said police.
A man who police say is a "witch doctor" and his wife are the prime suspects, the Fiji Sun reported Friday.
The crying baby, Samaira Kumar, 1, was found by Kelera Toloi, 25, the BBC reported.
"By the looks of it, she was hungry but I wonder what inhumane mind could have done such a thing," the BBC quoted her as telling the Sun. “Fortunately she did not walk or she would have fallen off the cliff."
The victims have been identified by local media as Nirmal Kuma, a 63-year-old carpenter, his wife Usha Devi, 54, their daughter Nileshni Kajal, 34, and Kajal’s two daughters, Sana, 11, and Samara, 8. They were found Monday in the Nausori Highlands.
Samaira was Sana and Samara’s cousin.
Fiji Police on Wednesday blamed the deaths on “an alleged harmful substance.”
The suspects were questioned for two days and released, according to reports. A court refused a police request to detain them longer.
Although they have been released, they can’t leave the country, a police officer told the paper.
“We released the man, who we have been told is a witch doctor, [Wednesday] and we will release the woman when her 48 hours expires [Friday],” the officer was quoted as saying.
“They are our prime suspects right now," the officer said. "According to the evidence that we have, we tried to exhaust all avenues to keep them in custody longer for questioning in connection with the five deaths.
The man who was questioned was an alleged "healer" who on three occasions in the past had treated Devi for stomach pains with herbal medicines Stuff NZ reported Friday.