An American citizen arrested last year in Saudi Arabia has been sentenced to 16 years in prison for several “light tweets” criticizing the government of Saudi Arabia, according to The Associated Press, citing news.ro.

Saad Ibrahim Almadi, a 72-year-old retired project manager living in Florida, was arrested last November while visiting family in the kingdom and was sentenced earlier this month.

Almadi is a citizen of Saudi Arabia and the United States.

Deputy State Department spokesman Vedant Patel, speaking to reporters in Washington, confirmed Almadi’s detention on Tuesday.

“We have consistently and intensively expressed our concerns about this case at the highest levels of the Saudi government through the channels of Riyadh and Washington, D.C., and will continue to do so,” he said.

“Just yesterday we raised this issue with members of the Saudi government,” the official added.

It appears to be the latest in a series of cases in which Saudis have received lengthy prison terms for social media posts critical of the government.

Saudi authorities have stepped up their crackdown on dissent since the ascension of Crown Prince Mohammed bin Salman, who is trying to open up and transform the ultra-conservative kingdom but has taken a tough line on any criticism.