The Special Task Force (STF), which is probing last week's murder of a journalist and his family in Umaria town here, wants to counduct narco analysis test and DNA profiling on the two arrested to collect "irrefutable" evidence in the case, sources said.

Highly-placed sources in the police department said on the condition of anonymity that since the STF wants a "foolproof" case against the accused, so that they do not get any benefit during the trial, efforts are on to collect "irrefutable" evidences in the case.

"The STF will apply for conducting the narco tests on the arrested persons, besides their DNA profiling and collect evidences by adopting more advanced technologies, so that they don't get any benefit during the trial of the murder case and subsequently get released," sources added.

They said that the involvement of two arrested persons Amit Singh and Vidhyaniwas Tiwari is clear and evidences collected from the crime site, will ultimately be proved against them on the basis of scientific probe.

"The STF is probing the case more in a scientific manner than the traditional one to build up its case against the arrested persons," they said.

Rai, his wife Durga, son Jalaj and daughter Nisha were found murdered inside their house on February 17 and the case was handed over to the STF for probe.

Two days ago, the STF had said that Rai was blackmailing a gang, who had recently kidnapped the son of a local PWD engineer. One of the kidnappers, Vidhyaniwas Tiwari, was Rai's neighbour. Rai had learnt who the kidnappers were, and had started blackmailing them, they had said.

"The kidnapping of the boy and the murder are linked to each other," sources said adding that Umaria police had "erred a little" in claiming earlier that the murder case has been solved.

They added that efforts are on to nab the absconding accused in the case. Meanwhile, state Congress chief Kantilal Bhuria today alleged that he had been told that apparently the mining mafia was also involved in the murder case and attempts are on to save "powerful people", associated with the mining mafia in the state.