DUBAI: Bahraini human rights activist Nabeel Rajab will face trial for tweets condemning the Gulf Arab kingdom’s prison system and its involvement in the war in Yemen, his lawyer said on Sunday, and he could face up to 13 years in prison.

Rajab was arrested earlier this month on unspecified charges in what appears an escalating crackdown by the Sunni-led government that also included a court shutting down a main opposition society and a decision to strip the spiritual leader of the island’s Shia Muslim majority of his citizenship.

Jalila Sayed, Rajab’s lawyer, told supporters in an email that he faces a prison term for tweets he made last year accusing security forces of torturing detainees in a main prison and of killing civilians in a war led by Saudi Arabia in Yemen.

“He was notified of the referring of his case regarding Jaw prison and the Yemen war to the High Criminal Court for trial,” Sayed wrote. “The first hearing will be on July 12. Nabeel may face up to 13 years of imprisonment if convicted in that case,” she added.

There was no immediate comment from Bahraini authorities regarding the case. Officials there deny systematic abuses of human rights and have accused the opposition of stirring sectarian hatred in the kingdom and serving the interests of their rival, Iran.

Rajab has repeatedly been arrested since 2011 pro-democracy protests mainly by Bahraini Shias were repressed with help by Saudi Arabia.

The kingdom hosts the US’s Fifth Fleet and is considered by Sunni-ruled Gulf kingdoms as a strategic bulwark against Iranian influence in the Arab world.