A Saudi man in Morocco faces extradition back home where he fears torture and a possible death sentence after being detained in the North African country, his brother said Saturday.

Hassan al-Rabie, 26, was detained on January 14 following an international notice sent by Saudi Arabia in November calling for his arrest on terror-related charges, his brother Ahmed, who resides in Canada, told AFP.

He accused the authorities of seeking to take his brother "hostage" in a bid to reveal the whereabouts of their brother Munir, a rights activist and vocal critic of the Saudi authorities.

Rabie was arrested while attempting to leave Morocco for Turkey, his brother added.

The notice, seen by AFP, showed Rabie had been accused of collaborating with a "terrorist to facilitate his (own) departure from the kingdom in an unregulated manner".

Saudi authorities frequently level terror charges against dissidents.

Rabie hails from Al-Awamiyah in the east of the kingdom, a Shiite-majority town that previously saw clashes erupt with the authorities in 2017 over plans to develop the area.

Shiites in Saudi Arabia have long complained of marginalisation by the Sunni-majority kingdom's authorities.

"Hassan is innocent and has nothing to do with these events," his brother told AFP.

Hassan al-Rabie was previously arrested in February 2021, along with two other brothers, Ahmed told AFP.

Two of the three brothers were released days later, but the eldest, Ali, was held and eventually sentenced to death last November, he added.

Hassan fled Saudi Arabia in late 2021 and spent time in Indonesia, Oman and Ukraine before settling in Morocco in November 2022, his brother said.

"I fear for Hassan's life if he is extradited to Saudi Arabia," he added. "The regime only deals in executions."

In March 2022, Saudi authorities executed 81 people, many of them Shiites, in a single day after they were convicted on terror charges.

Saudi authorities did not immediately respond to requests for comment on Rabie's case.

A Moroccan police source meanwhile told AFP that the decision on whether to extradite him would be determined by the court of cassation, without providing further details.

On Thursday, Human Rights Watch called on the Moroccan authorities not to extradite Rabie, citing "the rampant torture and due process violations in Saudi Arabia's criminal justice system".