KRUGER NATIONAL PARK, South Africa — Four national parks employees have been arrested in connection with the killing of two rhinos at South Africa's Kruger park, a famous safari destination that has been hard-hit by the rhino poaching crisis.

The carcasses of a white rhino cow and her calf were discovered Tuesday morning by tourists in the Pretoriuskop section of the park, where 11 rhinos have been killed since the start of 2012. The animals' horns had been removed.

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The four South African National Parks (SAN Parks) staff members were arrested hours after the dead rhinos were discovered, following an investigation by rangers and South African police that involved the specialized K9 Unit for Endangered Species.

SAN Parks has been trying desperately to stop the poaching epidemic, hiring extra rangers at Kruger park and having South African soldiers patrol key areas. But so far the problem has only increased, with 2012 on track to be the worst year yet for poaching.

The poaching is said to increase when the moon is waxing, as it is now, with the bright moonlight helping poachers to target rhinos overnight.

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The latest dead rhinos were found along the Napi Boulders Loop by tourists traveling in an open-air safari vehicle, SAN Parks said in a statement. Rangers and police were alerted, and rushed to the scene.

One of the employees arrested is a field ranger who is also involved in a strike against SAN Parks. Another of the suspects in a traffic cop at the park, while the other two are said to be guides, according to Kruger park staff.

A total of 80 rhinos have been lost to poaching in South Africa since the start of the year, including 43 in the Kruger park.

"It is a very sad day for South Africa to find out that the unscrupulous and revolting hands of the poaching syndicates have stretched as far as to taint the hands of those trusted with the great responsibility of being guardians of our natural heritage" said David Mabunda, chief executive of SAN Parks.

"I am personally saddened to discover that some of our own would so callously abuse the confidence and faith that we have entrusted upon them, he said.

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