A South African activist who spoke out against attacks on white farmers has been found stabbed and beaten to death on her own farm.

Annette Kennealy, 51, was killed on a smallholding in Limpopo province on either Monday night or Tuesday morning where she had been staying with an employee, police said.

The alarm was raised by Ms Kennealy's mother, Kim Labuschagne, after she tried and failed to get in touch with her daughter on Tuesday.

A male relative then went to the farm where Ms Kennealy's body was found face-down in a pool of blood.

Annette Kennealy, 51, a farmer activist from Limpopo province was beaten to death with a hammer and iron rod

Kennealy was a publicly outspoken supporter of the white Afrikaner community and former councillor with South Africa's opposition Democratic Alliance party

Police spokesman Colonel Moatshe Ngoepe said Ms Kennealy was found with 'multiple stab wounds'.

Marius Mueller, director of Afrikaner campaign group AfriForum, told Marelo Media that Ms Kennealy had been found with head wounds.

She was found laying on her stomach, had wounds to her left eye and an open wound on her forehead, he said.

A hammer was found next to the body alongside an iron rod, he added.

Another police spokesperson, Col Moatshe, said that a 40-year-old male suspect has been arrested and will soon appear before the Louis Trichardt Magistrate Court.

Kennealy made one last Facebook post about farmer attacks before she was murdered

Kennealy's last two Facebook posts were about attacks on white farmers this year

Kennealy was a publicly outspoken supporter of the white Afrikaner community, a prominent farmer and a former councillor with the opposition Democratic Alliance.

In her last Facebook post, she shared a link alleging that 10 farm attacks, including one murder, had been reported in four days in 21019.

She also routinely shared links and stories relating to politics in South Africa, and the government's plans to start expropriating farms from white land-owners.

A DA spokesman in Limpopo paid tribute to her as news of her death spread, saying: 'The DA asked for justice to be served on those responsible for her untimely and gruesome murder.

'Ms Kennealy served the DA as a councillor between the years 2011 and 2014 and will be remembered for her selfless service and her commitment towards human rights.

'The DA would further like to express sincere gratitude to the South African Police Service and community institutions for their swift and professional reaction.

'We hope that those responsible will soon have their days in court and that justice will be served.'

Cyril Ramaphosa has pushed ahead with changes to the constitution which mean land can be expropriated without any compensation being offered

The attack took place on the woman's own farm in the town of Louis Trichardt where she was staying with an employee

South Africa's ruling party, the African National Congress, has denounced the violence against farmers, but farming groups still accuse the party of not doing enough to stop it.

Ms Kennealy murder comes as the government, led by Cyril Ramaphosa, pushes ahead with plans to alter South Africa's constitution to allow land to be seized from farmers without having to compensate them.

Ramaphosa has said that such a move is necessary to compesate for the 'historical imbalance' caused by apartheid and colonialism.

Under Section 25 of the old constitution, citizens were granted the right to property which could be expropriated - but only upon payment of compensation.

The power of government to seize land was also limited, meaning that the majority of farmland remained in white hands - despite the majority of South Africa's population being black.

According to a 2017 census, 72 per cent of land was owned by white people, who made up just nine per cent of the population.

However, in December last year parliament voted 209-91 to amend the constitution to say that land could be expropriated without anything being paid in certain circumstances.

According to a police spokesperson, Col Moatshe, a 40-year-old male suspect had been arrested and will soon appear before the Louis Trichardt Magistrate Court

Ministers are now preparing a series of 'test cases' for the courts, despite warnings that it could take a decade or more to resolve the issue.

The ANC has sought to reassure people inside and outside the country that its efforts to ensure the majority of black South Africans have better access to land - a long-standing party promise - will be legal and should not be cause for alarm.

Ramaphosa has said everyone should 'relax' about the land reform process and that it would 'end up very well'.

Political parties and NGOs have criticised the government's attempts to change land reform measures.

The issue did not appear to play well for Ramaphosa at South Africa's recent election, the first since he seized power from predecessor Jacob Zuma, which the ruling ANC party won - but with a reduced majority.

Transvaal Agricultural Union, a group representing the interests of farmers, recorded 84 farm murders in the 2017 calendar year. Of these, 59 victims were white farmers.

A further 15 people, including eight white farmers, were killed on farms in the first three months of 2018.