A prominent Muslim scholar has been detained by Saudi Arabia for the past four months without charge, Human Rights Watch (HRW) said.

Saudi authorities detained Salman al-Awda on 7 September  and later imposed travel bans on members of Awda’s family, the US-based rights group said on Sunday.

A family member told HRW that Awda was being held over his refusal to comply with an order by Saudi authorities to tweet a specific text to support the Saudi-led blockade of Qatar.

Instead, Awda posted a tweet on September 9, saying: “May God harmonize between their hearts for the good of their people” – an apparent call for reconciliation between the Gulf countries, HRW said in a statement.

“Crown Prince Mohammad bin Salman’s efforts to reform the Saudi economy and society are bound to fail if his justice system scorns the rule of law by ordering arbitrary arrests and punishments,” said Sarah Leah Whitson, Middle East director at HRW.

“There’s no justification for punishing family members of a detainee without showing even the slightest evidence or accusation of wrongdoing on their part.”

Saudi authorities imposed travel bans on 17 members of Awda’s family, according to HRW.