The custodian of a local shrine and his accomplices have killed 20 devotees after intoxicating them in Pakistan, police say.
Officials said the incident in eastern Punjab province was the outcome of a dispute over custodianship of the shrine.
The shrine custodian in a village near the city of Sargodha, some 200 miles north of Multan, has been arrested along with four others for killing worshippers with batons and knives, senior police officer Mohammad Bilal said.
He said another four people are in a critical condition.
The victims were killed while naked, with the bodies bearing multiple stab wounds and blunt weapons marks, a doctor at Sargodha hospital told Geo TV.
Liaquat Ali Chatta, area government administrator, said Abdul Waheed and his four alleged accomplices were arrested and the matter is being investigated.
He said Waheed is a retired government employee and seemed "mentally unstable". He said the custodian was allegedly involved in the practice of "beating and torturing" devotees to "cleanse" them.
Mr Chatta said Waheed had confessed to the murders.
Zulfiquar Hameed, regional police officer for Sargodha and surrounding districts who is heading the probe, said the main suspect's confession and other statements suggest the incident was the "outcome of jealousy and dispute over custodianship" of the shrine.
"This man was afraid of losing prominence and that the position would go to somebody else," he said. "The issue of custodianship ends to this level of incident."
Rana Sanaullah, law minister for the Punjab provincial government, said an initial investigation showed that Waheed had a collection of followers who would regularly visit the shrine and face torture in the name of religious cleansing.
The shrine was built about two years ago on the grave of local religious leader Ali Mohammad Gujjar.
Shamsher Joya, a local police officer, said Waheed would come to the shrine twice a week from Lahore, and his followers would submit to "beating and torturing with a red hot iron rod".
Mr Joya said Waheed divulged during the investigation that he had acted to kill the victims after unearthing a plot to poison him.
Waheed alleged the plot was hatched by Asif Gujar, only son of the religious leader buried in the shrine, according to Mr Joya.
The 35-year-old Mr Gujjar is among the 20 victims.
Police said the victims were killed at a house adjacent to the shrine and their clothing was found burned.