Bahrain has freed prominent dissident Nabeel Rajab after spending two months in jail for insulting the authorities, for health reasons, official news agency Bahrain News Agency *BNA said.
King Hamad issued a royal decree granting Rajab, who was sentenced to six months, a special pardon, the agency reported late on Monday.
An appeals court in Bahrain in May upheld a six-month sentence imposed for a tweet published in September 2014 deemed insulting to the kingdom's security establishment.
Rajab, one of the Arab world's best-known democracy activists, was convicted of "publicly insulting two government bodies," the attorney general's office was quoting as saying at the time, referring to the defence and interior ministries.
Rajab has been a leading figure in democracy protests by the kingdom's largely Shia Muslim opposition since the 2011 "Arab Spring" uprisings.
The kingdom denies it discriminates against Shias and says it has rolled out reforms and is monitoring for abuses by the security forces.
Rajab was freed in May 2014 after serving a two-year jail sentence for his role in the protests. Rajab was also sentenced to three months in jail in 2013 in a separate case over a tweet criticising the prime minister, the king's uncle. The ruling was quashed, but only after Rajab had already served his sentence.