Saudi Arabia has sentenced prominent human rights lawyer Walid abu al-Khair to 15 years in prison on charges that include seeking to undermine the state and insulting the judiciary, the state news agency reported.
The Specialised Criminal Court on Sunday also found al-Khair guilty of "inciting public opinion" and barred him from travelling outside the kingdom.
Abu al-Khair had been on trial on sedition charges that included breaking allegiance to King Abdullah and for showing disrespect for authorities.
The rights lawyer's websites were also closed down and was he was fined $53,000 for activities related to his activism.
Abu al-Khair, the founder and director of the Monitor of Human Rights in Saudi Arabia, had been highly critical of a new anti-terrorism law passed by Saudi Arabia at the start of the year which was widely condemned by rights activists as a tool to stifle dissent.
The anti-terrorism law states that terrorist crimes include any act that "disturbs public order, shakes the security of society, or subjects its national unity to danger, or obstructs the primary system of rule or harms the reputation of the state".
Apart from Sunday's conviction, al-Khair had been sentenced by a Jeddah court last October to three months in jail for signing a petition in 2011 against the imprisonment of a group of activists demanding political reforms.
In October, he was sentenced to three months in prison for "insulting the judiciary" and a petition he signed two years ago criticising the authorities.
That same month he was briefly held for setting up an "unauthorised" meeting place where pro-reform activists gathered, but was later freed on bail.
In June 2012, he was accused of "disrespecting the judiciary... contacting foreign organisations and signing a petition demanding the release of detainees," some of whom were being held for suspected terror links, his wife said at the time.
Three months earlier, authorities banned him from travelling to the United States where he was due to attend a forum organised by the State Department.
And in February 2011, he signed two other petitions demanding political reform in the kingdom, where political parties are banned.
In the past year Saudi authorities have been criticised by international rights groups for jailing several prominent activists on charges ranging from setting up an illegal organisation to damaging the reputation of the country.
The world's top oil exporter has regularly dismissed criticism of its human rights record by Western countries and campaign groups.