New York based human rights group, Human Right Watch (HRW) reported on Friday that both Nepali police and protesters used extreme violence during the protests against the country's new constitution.
Based on the report which was released on Friday by HRW, 45 people have died, including nine police officers in the clashes that took place between August 24 and September 11 in five Terai districts.
According to the Human Rights Watch, there was "No evidence that any of these victims, including the police, was posing a threat when they were killed.”
"There is, in short, compelling evidence of criminal attacks on defenceless police by protesters, and abundant evidence in several cases of serious crimes by police against protesters and bystanders, including disproportionate use of force and extrajudicial killings," the report said.
The rights group urged Nepal to review its security policy to make sure that the security forces do not use excessive force against the protesters.
They also demanded that the Nepalese government assign an independent body to investigate the violence and hunt the perpetrators.
Group also said protest leaders should make sure that the protests are peaceful.
Reports indicated that police shot Nitu Yadav who was 14 years old "dead in the face at point-blank range" as he was hiding behind bushes..
"Doctors who subsequently examined Yadav's body confirmed that it bore injuries consistent with this account," the report said.
According to home minister, who underlined that he has not read the report, security forces in Nepal do not use force against peaceful protesters.
"Our law is that police and armed police may not use force against peaceful protesters," he said.
"But, when the protests are violent, and people are throwing petrol bombs at the police, then they have to make sure of their own safety," he added.
The violence escalated after the lynching of police assistant sub-inspector Thaman Bishwokarma, who was killed by protesters in Mahottari.
Following the violence, main part of Southern Nepal has remained under curfew since August 24.