https://proudstars.blogspot.com/2015/11/nigeria-police-force-releases-numbers.html
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you can call to report erring policemen
If you feel any policeman passed their boundary, then you now have a number to call & report them. The numbers are also if you need the help of the police. Read their statement below...
In furtherance to the Inspector-General of Police, IGP Solomon Arase’s resolve to improve on the Force internal accountability mechanisms, enhance service delivery and make policing more transparent and community based, the following help lines; Provost Marshal - 09053872207, Control-Room - 09053872208, X-Squad - 09053872209