One of the policemen deployed to quell the riot which broke out during the #EndBadGovernance protests in Kano openly threatened to kill protesters.
Kano was one of the places where the protest took a violent turn as hoodlums broke lose, looting both government agencies and private establishment.
A mob that tried to perpetrate violence at Government House, Kano, was forcefully dispersed.
Governor Abba Kabir Yusuf later declared curfew to check the widespread violence.
However, despite the curfew, some protesters returned to the streets, daring security operatives.
In one of the trending videos on the breakdown of law and order, a policeman, who spoke in Hausa, was heard threatening the protesters.
"Keep looting. Is it because I did not do what I had done to them? Those throwing stones should not stop. I swear to God, if police officers bleed, I will kill. I swear to God I will kill."
On Saturday, leadership of the organised labour warned the Nigeria Police Force and other security forces to stop what it described as "massacre" of protesters carrying out nationwide demonstration against hunger.
Weighing in on the situation, President of Nigeria Labour Congress (NLC), Joe Ajaero, questioned the professionalism of the police under the leadership of Inspectror-General Kayode Egbetokun.
"With unconfirmed reports putting casualties at 40+ in two days of managing the the EndHunger protest across the country, we have sufficient reasons (backed up by reports and video clips) to call to question the professionalism of our security personnel as this represents nothing but MASSACRE of citizens.
"We are deeply saddened by this wanton taking of life by trigger-happy police personnel. In Asokoro, Abuja under the command of Compol Bennett Igweh, protesters were heard querying why the police were shelling or tear-gassing them as they were marching solemnly without breaking a twig.
"One noticeable pattern was that once police personnel introduced violence, all hell broke loose in fulfilment of the credo that violence begets violence. We pause to ask, what happened to all the years of training or experience?
"No lessons learnt or was this a case of loss of human values on an industrial scale? Don't our police personnel watch their colleagues in other parts of the world manage equally challenging (if not worse) situations?"
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Similarly, former Vice-President Atiku Abubakar condemned the shooting of protesters, saying it was a reminder of the dark days of the military.
Amnesty International had said at least 13 people have been killed during the protests, mostly by the police and other security agencies.
However, the police said seven people were killed during the protests, none of them by security operatives.
