South Africa's security services have been accused of hacking a politician's phone after a sex tape emerged.

The 13-second video of Home Affairs Minister Malusi Gigaba masturbating on his own was widely circulated.

His spokesman accused security services of stealing the video from his phone and he accused an opposition politician of leaking it.

The spokesman said that the minister had started getting blackmail threats last year.

On Sunday Mr Gigaba apologised on Twitter to his family.

My wife and I have learned, with regret and sadness, that a video containing material of a sexual nature, meant for our eyes only, which was stolen when my communication got illegally intercepted/my phone got hacked, in 2016/17, is circulating among certain political figures...

— Malusi Gigaba (@mgigaba) 28 October 2018

I take this opportunity to publicly apologise, in advance, to the rest of my family - especially my kids, my mom and my in-laws - and the South African public for the pain and embarrassment the likely wider distribution of this private material will cause...

— Malusi Gigaba (@mgigaba) 28 October 2018

The video is being shared widely on WhatsApp among South Africans, the BBC's Milton Nkosi reports.

Mr Gigaba said he had refused to entertain blackmail attempts.

These blackmail/extortion attempts as well as the illegal interception of my communication/hacking of my phone have all been reported to the relevant law enforcement/intelligence agencies and I am advised that the resultant investigations are still continuing...

— Malusi Gigaba (@mgigaba) 28 October 2018

His spokesman, Vuyo Mkhize, told public broadcaster SABC that 10m rand ($690,000, £540,000) had been demanded.

"The state security agency was behind the illegal interception of the minister's communication/retrieval of the video from his phone," he tweeted.

This is not the first time Mr Gigaba's sex life has filled South African newspapers. Times Live reminds its readers that his wife had a public spat with his mistress in 2015.