Jolly was arrested only in the case relating to the death of her husband in 2011.

Kerala police Chief Loknath Behra on Saturday expressed satisfaction over the ongoing probe into the case relating to the mysterious deaths of six members of a family near here. Mr Behra, who reached Vatakara to assess the progress of the preliminary investigation, said six teams would conduct inquiries.

"There are six murders and six cases. The first death happened in 2002. We will have to collect evidence. Will have six probe teams and the SP will head the supervisory team. We will discuss the matter with legal experts," Mr Behra told reporters.

He further said the investigation was all about collecting evidence of the crime which had happened over the years.

Noting that it was a "challenging case", the the police official said, "... We will be discussing with the forensic team. They might suggest conducting various tests."

"Earlier, there was no case. Then we got the complaint. Now the preliminary probe is going well. This is a team work. We will provide all neccessary help to the probe team," he said.

Eight years after the death of her husband Roy Thomas following consumption of cyanide-laced food, 47-year-old Jolly and two others were arrested on October 5 and investigation began into the deaths of five others in the family. Two other accused--MS Mathew (44), a close friend of Jolly and Prajikumar (48) had allegedly supplied cyanide to Mathew, who handed it over to Jolly.

Jolly was arrested only in the case relating to the death of her husband in 2011 due to the presence of cyanide mentioned in his post-mortem report. The SIT is probing the case after receiving a complaint

from Mr Roy's US based brother, Rojo, over the six deaths between 2002-20.

The probe team had yesterday taken Jolly to the Ponamattil house, where three deaths had taken place-- Annamma (2002), Tom Thomas (2008), parents of Roy who died in 2011 after consuming some food in the house.

Jolly married Roy's relative Shaju in 2017.

Besides, the deaths of three other members of the family-- Roy's uncle Mathew (2014), relative's wife Sili and her one year-old daughter-- are also under the police scanner.