South Africa's army and police were called in Thursday to rescue residents from thousands of crocodiles that escaped from a farm whose floodgates were opened due to torrential rains.

Around 15,000 predators sprung from the Rakwena Crocodile Farm in the far north of the country when owners were forced to open the gates to prevent a storm surge, local daily Beeld reported.

A number have since been recaptured, but at least half remain on the loose, scattered far and wide.

Some turned up on a school rugby pitch 120 kilometres (75 miles) away.

The surrounding province of Limpopo province has been hit by serious floods which have killed 10 people and made many more homeless.

"Before there were only a few crocodiles in the Limpopo River. Now there are plenty," said Zane Langman, the son-in-law of Rakwena's owner.

"We go catch them when farmers phone us and say crocs are around."

Langman earlier used a motor boat to rescue some local residents who had climbed onto the roof of a garage to escape the rising floods.

"When we arrived there, the crocodiles were circling them," he said.

The army has been called in to help track down the reptiles, according to police spokesman Hangwani Mulaudzi.

"Police, the army, and people from the community are assisting," he said.

No incidents involving crocodile attacks have been reported, he told AFP.

Hundreds of kilometres downstream the Limpopo River floods have also savaged neighbouring Mozambique, were tens of thousands of people were being evacuated from their homes.