Authorities in Alexandria township in South Africa have come up with a novel idea to cope with an overpopulation of rats in the area – award residents with a free mobile phone for every sixty rodents they kill.

According to a report in South Africa's Mail & Guardian newspaper, Alexandria township, a poor suburb of Johannesburg, rats have overrun the region, attracted to open sewers  and piles of rotting food. The pesky rodents become a particular problem in the evening.

“The place comes alive at night,” local resident Leo Ndabambi told the paper.

“People come home and start cooking in the evening. When they throw the leftovers away with their rubbish the rats stream out of their holes.”

Killing rats has emerged as a popular sport, especially among children.

“It’s easy,” one young man bragged. “You put your left-over food inside and the rats climb inside, getting caught as the trap door closes.

“They are so dangerous for our community. You hear of children getting bitten, and when you walk at night you always step on them. So anything to kill them helps,”

As a consequence, 8ta, the mobile phone company has reportedly offered a cellphone to people who can capture six dozen rats.

Local municipal officials support the scheme.

Councillor Julie Moloi said: “We are afraid that these rats will take over [Alexandria] and it will become a city of rats. “We need to educate people... about how the food they dump causes the rats to grow.”

Officials are also using owls and fumigation to control the exploding rat population.

An infestation of rodents has become a health concern in other urbanized parts of South Africa.

“In the presence of dense human settlements, a steady supply of food waste and the absence of predators, they will never really be eradicated,” warned Councillor Lungiswa James, a mayoral committee member for health in Cape Town.

However, the Daily Telegraph newspaper of Britain reported that 8ta denied any responsibility for the rat-killing program, citing that a charity called Lifeline which it had sponsored is handing out the free phones.

"You will have to ask Lifeline why they decided to use these promotional products," said Pynee Chetty, an 8ta spokesman.

"They do a lot of good community work, including in Alexandra. They used the promotional material to incentivise members of the community. I wasn't aware this is how they were going to resolve the problem [of the rats]."

He also said: "We won't distance ourselves from Lifeline. It is a charity that does a lot of good work and our support for them is steadfast. I don't want to deny the story. What I'm saying is that it's not our initiative."