Fijian police have charged a New Zealand man with five counts of murder following the mysterious "witchcraft" deaths of a family last month.

Key points: Five family members were all found dead in the Nausori Highlands in August

Five family members were all found dead in the Nausori Highlands in August No visible injuries were present on the dead, with local police suspecting poison as their cause of death

No visible injuries were present on the dead, with local police suspecting poison as their cause of death A one-year-old baby found alive at the scene and referred to in Fijian media as the "miracle baby" has since been released from hospital

Husband and wife Nirmal Kumar, 63, and Usha Devi, 54, their daughter Nileshni Kajal, 34, and Ms Kajal's daughters Sana, 11, and Samara, eight, were all found dead in the Nausori Highlands last month.

According to reports and police testimony, a one-year-old baby was found alive among the bodies.

The case has transfixed and shocked Fijians.

With no visible injuries present on the bodies of the five family members, police have suspected poisoning as their cause of death.

The father of the two dead children told the Fiji Sun that his father-in-law, also among the deceased, was interested in witchcraft.

"I never saw anyone or any family so much into witchcraft than my in-laws," he said.

"I used to see my in-laws and other witchdoctors making a doll from dough and poking needles in it. I always took my daughters away into the bedroom.

"My wife and daughters were obviously also dragged into it."

On Monday, three weeks after the bodies were found and after the ordering of toxicology reports, police laid charges.

The suspect — who has permanent residency status in New Zealand — and his wife had been questioned by police last month, with a court order issued to prevent the pair leaving Fiji.

He was due to appear at Nadi Magistrates' Court on Monday over five murder charges and one attempted murder charge.

The child found at the scene, referred to in Fijian media as the "miracle baby", has since been released from hospital.

AAP