Officials at a wildlife park in Kenya say they found four dead rhinoceros shot by poachers in a two-day span.

The Lewa Wildlife Conservancy said Wednesday that two male black rhinos and two female black rhinos were killed. The bodies were discovered on Saturday and Sunday. Lewa has lost 10 rhinos to poaching in the last three years.

Poaching deaths of rhinos and elephants are spiking sharply across Africa because of an increase demand for rhino horn and ivory from Asia's rising middle class.

The four deaths bring Lewa's rhino population to 71. Lewa is a private reserve near Mount Kenya.

Kenya has about 600 rhinos in total.