Paul Oparaji is the chairman of a local neighbourhood watch group in Enugu - quite normal for a pensioner, one might think.

But in Nigeria "neighbourhood watch" means taking to the streets with a gun or machete and possibly lynching armed robbers.

At an age where other men are keen to put their feet up and enjoy the company of their family, Mr Oparaji is a vigilante, prepared to dispense what he calls "jungle justice".

"Imagine myself, at 73 I haven't had a full night's sleep in eight years," he says.

"But if I don't do it, and robbers come here, my family and I will be maimed."

Every night at around 2230, he and 18 other men strap their ancient shotguns to their backs and walk through their neighbourhood banging a large metal bell to let the people in their houses know someone is watching over them, and let the robbers know someone is coming.

'Magic cutlass'

This "informal policing" happens in cities across Nigeria. The vigilantes are the only ones that stand between robbers and residents.