With killings at "crisis levels", wildlife authorities in South Africa's Kruger National Park announced on Wednesday they would give substantial cash rewards for tipoffs about rhino poaching.

Unveiling a five-year plan to reduce poaching by 18 percent a year, South African National Parks (SANParks) said those providing information leading to the prosecution of poaching syndicates would receive a $115,000 (90,000-euro) reward.

A $12,000 reward will be given for information leading to the arrest of a poacher.

"In Kruger poaching has reached crisis levels, we are losing one rhino a day," SANParks boss David Mabunda said as he announced the plan, which will also rely heavily on technology.

"Our strategy is to reduce poaching by between 10 percent to 18 percent every year for the next five years."

"We would like to see zero killings, but we understand that that is impossible," he said.

With 618 rhinos killed so far this year, 383 inside Kruger, officials also want to increase cooperation with Mozambique, which borders the two-million-hectare (five-million-acre) park.

It is projected that before the end of the year 22 more animals will be killed in the park, which boasts 40 percent of the world's rhino population.

"The active poaching corridor in the Kruger Park is the Mozambique corridor," Mabunda said, adding that syndicates were offering impoverished villagers large sums of money to kill rhinos.

"It is hard to pursue people once they have crossed the border to Mozambique, where our people have no jurisdiction to arrest them," Mabunda said.

The park has recently acquired a military aircraft equipped with sophisticated surveillance technology to detect poachers.

The aircraft will assist the increased teams of rangers and members of the army who have been deployed to the park to fight the scourge.

Mabunda said the goal was to reduce poaching to pre-2008 levels. Only 10 rhinos were killed in 2007 in the country's top safari destination, visited by more than a million people every year.

The new technological expertise and other resources ploughed into the park to curb rhino poaching are expected to be useful in fighting new poaching trends which may arise in future, Mabunda said.

"Elephants are being killed in other parts of the continent, we are likely to see that trend coming down here. So the knowledge we have gained will not be only limited to fighting rhino poaching," he said.

Rangers at the park come under fire from highly organised syndicates who make use of automatic weapons to carry out the killings.

Mabunda said 20 incursions were detected in the park every day.

Rhino poaching is driven by a booming demand for their horns, which are wrongly believed to have powerful medicinal properties in some Asian countries.

Only the black and white rhino species are found Africa, and environmentalists claim that the black rhino is becoming critically threatened, with less than 5,000 in the wild.

This week South Africa and Vietnam signed a deal to tackle the trade, but Mabunda said it was too early to tell if it would have any impact

South Africa is one of the continent's leaders in nature and wildlife conservation, with 20 public reserves managed by SANParks. Kruger officials said they could not put a number on the cost of anti-poaching initiatives for SANParks coffers.