Manipur Chief Minister N Biren Singh on Thursday evening said two persons were arrested in connection with the May 4 incident in which two women were paraded naked in Kangpokpi district by a mob.
Addressing a press conference, Singh said it was a crime against humanity.
"We will not spare anyone. All the legislators of the ruling BJP condemn the incident in the strongest possible terms. Will give exemplary punishment to all those involved, even go to the extent of seeking capital punishment," he said.
"I have just got the news that another person has been arrested in connection with the incident. Interrogation is going on," he added.
Earlier in the day, a man who was part of the mob that paraded naked the two tribal women and was seen dragging one of them was arrested as the incident of May 4 drew widespread condemnation.
Police said the arrested person was seen prominently directing the mob at B Phainom village in the 26-second video that surfaced on Wednesday, triggering an outrage.
Taking suo motu cognisance of the video, police last night said a case of abduction, gang rape and murder was registered at Nongpok Sekmai police station in Thoubal district against unknown armed men and that all-out efforts were on to arrest the culprits at the earliest.
During the night-long raids, supervised by senior IPS officers, the person identified as Huirem Heradash Singh, age 32, was arrested from Thoubal district while a manhunt has been launched to nab others.
The two women are alleged to have been sexually assaulted before being set free by the mob.