A crocodile killed a cow in Tonj River of Warrap State on Tuesday.
Wildlife Officer James Rel Yak said belonged to Tonj South former director Akoc Agoth, Don Bosco Radio reported.Mr Yak said last week crocodiles killed four goats along the river Tonj where they went to drink.
He urged Tonj South residents not to take their animals early in the morning or late in the evening to the river.
Mr Yak said he informed the prison authorities not to allow prisoners to bathe in the morning or evening in the river.
He added that Tonj River is home for crocodiles, hippos and other water animals.
Wildlife Director Valentine Deng Mangok said he reported the incidents with crocodiles to the State to Director General of Wildlife.
He added that he could not do anything about the animals eaten by crocodiles.