JAMSHEDPUR: West Singhbhum police have arrested 15 persons accused in the massacre of seven adivasi Christians at Burgulikera village. They will be sent to prison on Sunday, police said on Saturday. On January 19, seven villagers were beheaded in the village in a clash allegedly between pro and anti-Pathalgarhi activists.West Singhbhhum SP Indrajeet Mahata said, "All the 15 accused have accepted their involvement in the killings. During interrogation by special investigation team (SIT), they helped police secure crucial evidences relating to the murders."Out of the 15 accused, eight have been named in the FIR while the remaining were picked up on the basis of suspicion. "A memo of evidence helped us confirm the involvement of the suspects," Mahata said. He refused to make a comment on the motive for the killings and said police will make a formal announcement after the SIT concludes its probe.He added that the district police have set up a police picket under Gudri police station area and heavy security vigil is in place to prevent any possible flare up.