The authorities in protest-hit Sudan have refused to renew the accreditation from three journalists working for Al Jazeera, a journalist has confirmed to the BBC.

It means they will not be allowed to report on events in the country where anti-government demonstrations have entered their sixth week.

A reporter for Turkey's Anadolu news agency has also been blocked from reporting, as has a correspondent for Saudi-based Al Arabiya.

On Monday, the Sudanese authorities said they wanted to review the Anadolu and Al Arabiya journalists' status, but gave no further explanation.

Protests began in Sudan last month over the economic situation in the country but are now focused on removing long-time President Omar al-Bashir from office.

Officials say 26 people have died in the protests, but rights groups say more than 40 have been killed.