The National Human Rights Commission says security forces, including police and army, deployed to enforce the restrictions have been involved in deadly confrontations in some states of Africa's most populous country.
Nigerian security agents have killed 18 people in their enforcement of measures to curb coronavirus, a figure higher than the documented toll inflicted by the disease itself, the country's human rights body said.
Africa's most populous nation has imposed a total lockdown in megacity Lagos and the capital, Abuja, and set restrictions in other regions in a bid to contain the virus.
According to official figures, coronavirus has so far infected 407 people in Nigeria, 12 of them fatally.
Security forces, including police and army, have been deployed to enforce the restrictions, sparking deadly confrontations in some states.
In a report released late on Wednesday, the National Human Rights Commission said it had received and documented "105 complaints of incidents of human rights violations perpetrated by security forces" in 24 of Nigeria's 36 states and Abuja.
Of these complaints, "there were 8 documented incidents of extrajudicial killings leading to 18 deaths", it said.
'Excessive use of force'
The commission noted that the tally of killings was higher than the recorded toll from the disease itself.
"Whereas Covid-19 led to the death of 11 victims, law-enforcement agents extrajudicially executed 18 persons in the cause of the enforcement regulations," it said, referring to the official virus toll as at the time of the report.
It accused the security agents of "excessive or disproportionate use of force, abuse of power, corruption and non-adherence to national and international laws, best practices and rules of engagement".
Allegations 'too general'
National police spokesman Frank Mba said the commission was "too general in its allegations," saying it ought to have been specific in the number of people killed by the police.
"The commission should have given details of those killed by the police, their number, names and places where they were killed to enable us to take appropriate actions," he said.
He said the police would continue to enforce the lockdown measures "professionally and in line with international best practices."
He said the police authorities would not condone any abuses or infractions against the personnel, adding that recently an officer who extorted money from a civilian was punished and made to refund it to the owner.
Local and international rights bodies have long accused Nigerian security forces of abuses against civilians, but they have denied the charges.
There have been growing fears of a rise in crime and unrest due to the virus restrictions, especially in Lagos, as millions of people living in poverty have been cut off from vital income.