Deputy President Cyril Ramaphosa on Thursday condemned threats against members of parliament inquiring into allegations of State capture at power utility Eskom.

"We will not accept that people should be threatened and abused simply because they are doing their job, a job they were elected for," Ramaphosa told the parliamentary Press Gallery Association (PGA).

The deputy president lauded Parliament for starting to take its "activist" role seriously, referring to inquiries into the South African Broadcasting Corporation and Eskom.

"Such inquiries may make some people uncomfortable. They also portray sections of government in a poor light but they are vital in restoring the confidence of the people in the State as a whole," he said

Parliament on Wednesday said it was putting in place measures to ensure the security of MPs and staff members working on the Eskom inquiry.

In a statement, National Assembly Deputy Speaker Lechesa Tsenoli said Parliament was greatly concerned following threats made against inquiry chairperson Zukiswa Rantho, a ruling African National Congress legislator; Natasha Mazzone, an opposition Democratic Alliance MP; and Ntuthuzelo Vanara, the parliamentary law advisor acting as evidence leader.

"Parliament wishes to reassure the public that it is setting in motion certain processes to, amongst others, address the concerns and safety of those conducting the inquiry and the inviolability of the inquiry itself," Tsenoli said.

Rantho told the media her son was accosted by unidentified people and told: "Your mother is making our lives difficult."

Mazzone reported that she had been followed by a car and her vehicle broken into.

Vanara said in an affidavit submitted to Parliament he had been offered a bribe by State Security Minister Bongani Bongo in exchange for stepping down as evidence leader. Bongo has not commented on the accusation.