A Saudi court has sentenced 15 people to death for spying for the kingdom's archrival Iran, in a move that is likely to heighten regional tensions.
The court in the capital, Riyadh, also sentenced 15 other defendants to prison terms ranging from six months to 25 years. Two defendants were acquitted at the December 6 session.
Iranian Foreign Ministry spokesman Bahram Ghasemi denied that any Iranian spying had occurred in Saudi Arabia.
"Such accusations are baseless and serve political motives," he was quoted as saying by the semiofficial Tasnim news agency.
The charges against the group included establishing a spy ring in collaboration with Iranian intelligence, providing Iran with confidential information on the Saudi military, attempting to recruit moles in the government, and supporting "riots" in Shi’ite-majority areas in the kingdom.
Amnesty International, in a statement, described the sentences "a travesty of justice and a serious violation of human rights."
"Sentencing 15 people to death after a farcical trial which flouted basic fair trial standards is a slap in the face for justice," said Amnesty's Samah Hadid.
The 32 defendants included 30 Saudis from the predominately Shi’ite region of Qatif, one Iranian, and one Afghan national.
Ghasemi said Riyadh had not passed on "any information to the Islamic Republic of Iran regarding the alleged Iranian person" in the trial.
Saudi Arabia has blamed sporadic unrest among Shi'ites in Qatif, who claim to face persistent discrimination, on Tehran. Iran has denied any involvement.
Saudi media reported that many of the 32 were former employees of the Saudi defense and interior ministries.
They were detained in 2013 and went on trial in February. Among those arrested that year were an elderly university professor, a pediatrician, a banker, and two clerics.
The verdicts can be appealed.
The Sunni-ruled kingdom of Saudi Arabia and Shi'ite-led Iran are major rivals in the Middle East.
In January, Riyadh cut ties with Tehran after Iranian demonstrators torched Saudi diplomatic missions following Saudi Arabia's execution of a prominent Shi'ite cleric.