UN rights experts condemn Saudi Arabia's repression of activists

In a statement, they denounced a "worrying pattern of widespread and systematic arbitrary arrests and detention" of religious figures, writers, journalists, academics and activists through the kingdom's use of counter-terrorism and security-related laws.

"We are witnessing the persecution of human rights defenders for peacefully exercising their rights to freedom of expression, assembly, association and belief, as well as in retaliation for their work," the five independent experts said.

More than 60 prominent personalities were arrested in Saudi Arabia in September, with no reason given by authorities for their detention.

Among the those arrested was social media star and successful social entrepreneur Essam al-Zamel and the famous Saudi historian Dr Khaled al-Awda, who is also the brother of one of the kingdom's most famous clerics - Dr Salman al-Awda - who was also arrested.

Popular progressive Saudi journalist Jamal Khashoggi was also banned from writing for al-Hayat newspaper, a Saudi daily owned by the kingdom's royal family, following comments he made on social media defending the Muslim Brotherhood, which Saudi Arabia has blacklisted as a "terror group".

The crackdown on dissent has been denounced by Amnesty International and Human Rights Watch, but strong criticism by the UN of Saudi Arabia is rare.

Amnesty International has previously said the rights situation in the Gulf state had "deteriorated markedly" since Prince Mohammed bin Salman took over as crown prince and heir to the throne in June.

There was no immediate reaction from Riyadh, which has said it does not have political prisoners. Saudi Arabia's attorney general has previously warned that any attack on "national unity" or the "image of the state" amounted to a "terrorist crime".

Agencies contributed to this report.