RIYADH: The family of a Shia activist sentenced to death after protesting in Saudi Arabia has voiced concerns for his fate as a rights group warned of his imminent execution.

The sentence against Ali al-Nimr, who was 17 years old when he was arrested in February 2012, has drawn international condemnation over his young age and allegations that he was tortured.

Ali al-Nimr's uncle told AFP on Friday, November 27, his family fears "the government is serious, very serious" about carrying out the sentence.

Jaffar al-Nimr said that his nephew reported that he had undergone a medical check when his family last spoke to him two weeks ago.

Amnesty International warned Thursday that Ali al-Nimr was among more than 50 people, including other Shia activists, at increased risk of soon being put to death in a single day.

His mother and the mothers of other detainees implored King Salman for clemency after learning of preparations possibly associated with impending executions, the London-based rights group said.

Ali al-Nimr's case has provoked a call for clemency from France, while the United States expressed "deep concern."

Activists say Ali al-Nimr is one of three Shia protesters who were minors at the time of their arrest and have been sentenced to death. They have exhausted all appeals.

"International law prohibits the use of the death penalty against anyone under the age of 18," Amnesty said on Thursday.

It added that there were "credible allegations" the three youths had been tortured.

Their fate rests with King Salman who, activists say, must give final approval before death sentences are carried out.

The case of Jaffar al-Nimr's brother, Shia cleric Nimr al-Nimr, also rests with Salman after the Supreme Court last month upheld his death sentence for sedition.

"They are peaceful people," Jaffar al-Nimr said. "They are not criminals."

The sheikh was a driving force behind protests that erupted in 2011 in eastern Saudi Arabia, where most of the country's estimated two million Shias live.

The protests developed into a call for equality in the Sunni-ruled kingdom, where many Shias have complained of marginalisation.

Amnesty said Nimr al-Nimr was among six Shia activists at imminent risk of execution who were "clearly convicted in unfair trials."

The rights group earlier this month reported that a surge in executions in Saudi Arabia had pushed to 151 the number of people put to death this year.

In recent weeks, however, there has been a marked drop in the number of executions, all of which are reported by the official Saudi Press Agency.

Saudi Arabia's Foreign Minister Adel al-Jubeir on Thursday was asked about the case of Saudi blogger Raif Badawi, sentenced to flogging and 10 years in jail for allegedly insulting Islam.

"We expect other countries to respect our legal system," he said.

1,000 demand release of Saudi death row Shias

About 1,000 members of the Shia community gathered at a mosque on Friday to demand the release of activists on death row, including Ali al-Nimr, a resident said.

He said the prayers and sermons at Imam Hussein Mosque in the Eastern Province town of Awamiya drew Shias from nearby Qatif and the Al-Ahsa region.

“They gathered to demand their freedom,” said the resident who asked for anonymity.

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