A young Saudi man, arrested when he was 13, could face execution for taking part in Shia-led protests as a child, Amnesty International has said.

Murtaja Qureiris, now 18, is on trial for charges that include joining a “terror group” and “sowing sedition”, according to the rights group. He was detained in September 2014 and held in solitary confinement for part of the time since.

As is typical with cases involving national security, Saudi Arabia has not commented nor made public details of the case.

Concern, however, has grown after the kingdom as recently as April carried out a mass execution of 37 men, most of whom were Shia. Among those executed was a young Shia male arrested at the age of 16, according to Amnesty International. The rights group deemed the trial of some of those executed “grossly unfair”.

Qureiris is being charged with offences that involve taking part in protests when he was as young as 10. Another charge relates to his participation at the age of 11 in an anti-government rally that erupted at the funeral of his older brother, who was killed while protesting in 2011 during the height of Arab spring revolts that broke out in other parts of the Middle East.

Minority Shia protesters in Saudi Arabia’s Eastern province launched protests that year to demand equal rights and a greater share of the kingdom’s oil wealth, which is concentrated in the east. They complained of poor government services, as well as discrimination from the country’s government-backed ultra-conservative Wahhabi clerics and their Sunni followers.

In recent years, as tensions with Shia-led Iran have intensified, the government under King Salman and Crown Prince Mohammed bin Salman has also intensified a crackdown on government critics, particularly Saudi Shias.

Since 2014, more than 100 Saudi Shias have been tried before Saudi Arabia’s anti-terrorism court on vague and wide-ranging charges arising from their opposition to the government, according to Amnesty International. In 2016, the kingdom’s highest-profile Shia cleric, Sheikh Nimr al-Nimr, was executed, sparking protests from Pakistan to Iran and the ransacking of the Saudi embassy in Tehran. Saudi-Iranian ties have not recovered and the embassy remains shuttered.

Details of Qureiris’s case emerged after CNN reported that Saudi prosecutors had sought capital punishment for him in 2018. Prosecutors argued that his “sowing of sedition” warranted the worst possible punishment, even though he had not been charged with loss of life.

He has, however, been charged with shooting at security forces and accompanying his brother on a motorcycle ride to a police station in the mostly Shia town of Awamiya, where the brother allegedly threw a makeshift firebomb at the station.

CNN said Qureiris, whose father and brother are detained, has denied the charges, and activists say his confessions were obtained under duress.