A US citizen was sentenced to 10 years in jail in Bahrain on Tuesday on charges of attempted murder during a disturbance related to Shi'ite Muslim demands for greater rights.
Bahrain has seen almost daily protests by members of the Shi'ite majority since February 2011, when it quelled a Shi'ite led uprising demanding that the Sunni al-Khalifa dynasty give up power.
Tagi al-Maidan had earlier told Reuters the charges against him were false, but that he had made a false confession under torture after his detention in October last year.
The government has denied any abuse in the incident, saying it has a "zero-tolerance policy" towards torture.
"The sentence was 10 years. We will appeal as soon as possible," his lawyer Mohammed al-Jishi told Reuters.
"The sentence was unexpected. There is no conclusive evidence against Tagi."
A government official declined to comment until questions were sent to him by email.
The US Embassy referred questions to the State Department in Washington, which was not immediately available to comment.
Maidan's sister Noura, attended Tuesday's court session and said US consular officials had been present.
"After the sentence was read, Tagi was calm and he looked down towards the ground," she said. "He was in a state of shock."
Maidan was born in the United States to a Bahraini mother and Saudi father and his status as a US national has thrown a spotlight on the complex relationship between Washington and Bahrain.
The Gulf kingdom is a US ally in a volatile region and has long provided a base for the US Navy's Fifth Fleet; but at the same time it faces criticism over its record on human rights that the United States champions.
The persistent unrest has placed Bahrain on the front line of a struggle for regional influence between Sunni Saudi Arabia, Bahrain's close ally, and Shi'ite Iran, which denies Bahraini accusations of fomenting Shi'ite protests.
Bahrain's Shi'ites have long complained of entrenched discrimination in areas such as employment and public services, despite the denials of the Sunni-led government.
Local and international rights groups say many other Shi'ite Bahraini youths have been arbitrarily arrested and jailed since 2011 for alleged offences against Bahrain's security forces. The government denies making any arbitrary arrests.