Animal activists are offering a R40‚000 reward for any information that will lead to the arrest of people involved in the poisoning of a troop of monkeys in Umdloti‚ north of Durban.

Of the 22 monkeys found poisoned at an Umdloti home on Saturday‚ 13 of them did not survive.

Steve Smit‚ the founder of Monkey Hotline‚ which helps rescue monkeys and educate people about them‚ said he believed the animals were poisoned with bread laced with pesticide.

“When we got to a home in Umdloti‚ it was a horrible sight. There were monkeys lying all over the floor‚ foaming at the mouth‚ with some hanging off a tree‚ convulsing‚” he said.

Smit called the killing "malicious and deliberate"‚ adding that it was one of the worst incidents he had seen in 24 years.

He said the monkeys were taken to a veterinary clinic‚ where 13 could not be saved. He said he hoped that the remaining nine currently being treated could be released back into their natural habitat.

"Some of these monkeys were still very young. Now they have to grow up without mothers because of someone's selfish and intolerable actions‚" said Smit.

Marshall Security’s Kyle van Reenen said they were alerted to the poisoning via social media and knew they had to get involved. "When someone commits a crime against anyone in our community‚ whether human or an animal‚ we always try to to get involved and help out‚" he said.

Van Reenen said the company initially put up a reward of R20‚000 for information leading to the arrest of the perpetrator‚ but this has already increased due to offers of financial support from animal lovers.

"A local restaurant has just offered us another R5‚000‚ so the money is likely to go up‚" he said.