Police in India's Jharkhand state have arrested a tribal leader after reports that a tribal council ordered a couple accused of adultery to be lynched.
Ram Jadia is being held in connection with the killing of Jasmani Jadia, 31, and Kushal Lugun, her 20-year-old brother-in-law, on 12 January.
The couple, who belonged to the Munda tribe, were accused of killing her husband as well as having an affair.
Police say they were tied to trees and beaten to death in Simdega district.
Officers exhumed their bodies 48 hours after being told of the lynching.
Dev Kumar Dhan, a spokesman for local tribal chiefs, said anyone who committed adultery had to be stoned to death, according to tribal norms.
"We don't approve of the idea of people taking the law into their own hands, but it is their social practice," he told the BBC.
District police superintendent Saket Kumar Singh said villagers were reluctant to co-operate in the investigation.
"We have arrested the tribal headman, while a criminal case has been registered against the villagers for the murder," he said.
Police say even Jasmani Jadia's relatives are not ready to come forward to help, fearing they could be ostracised.
On Tuesday, tribal elders sentenced the person who tipped police off about the lynching to 50 lashes in public.
In another part of the state, tribal elders recently shaved the heads of a tribal woman and her husband because she married below her caste.
The couple were also banished from their village in Ranchi district.