The government also suspended the deputy commissioner and superintendent of police of Dimapur district for their failure to tackle the situation.
Nagaland Chief Minister TR Zeliang, who chaired a cabinet meeting Friday, said: "It is highly condemnable incident. The cabinet decided to suspend the deputy commissioner and superintendent of police of Dimapur district immediately for their failure to tackle the situation."
"The deputy commissioner and superintendent of police should have taken pre-emptive measures to contain the situation. But they have failed," he said.
Zeliang said fresh orders have been issued to all the deputy commissioners and superintendents of police in the state to protect the non-locals, particularly people belonging to minority communities.
The authorities have imposed Section 144 of the Criminal Procedure Code, which prohibits unlawful assembly, in and around the town and deployed additional security forces in all the sensitive areas.
One of the four protesters, who received bullet injuries during police firing on Thursday, breathed his last, police said.
Meanwhile, Chief Minister Zeliang Friday assured his Assam counterpart Tarun Gogoi that necessary action would be taken against the perpetrators, who broke into the jail and lynched the alleged rapist.
In a telephonic conversation, Zeliang told Gogoi that a judicial probe into the incident has already been initiated.