DUBAI - Bahrain freed opposition leader Ali Salman on Sunday, a day after his arrest, although it slapped a travel ban on the head of the Shiite Al-Wefaq bloc, the prosecution said.
Salman, head of the opposition Al-Wefaq bloc, had been questioned over accusations of "incitement to religious hatred and spreading false news likely to harm national security," attorney general Abdul Rahman al-Said was quoted as saying by the official BNA news agency.
The prosecution had ordered the release of the Al-Wefaq secretary general but "forbade him from any travel for the purposes of the investigation," he added.
During his detention, Salman had been asked about the content of a speech he gave on Friday.
The attorney general said Salman was suspected of "inciting hatred against a religious community" in the Sunni Muslim-ruled country during the address.
He was also alleged to have "accused institutions of the state of engaging in illegal practices".
The speech was followed by "disturbances, acts of violence and aggression against the security forces that caused injuries in their ranks," the chief prosecutor added.
Six opposition groups including Al-Wefaq have issued a statement denouncing Salman's detention as an "attack on freedom of expression in Bahrain".
Al-Wefaq, the most important opposition grouping in Shiite-majority Bahrain, wants a constitutional monarchy in the Gulf nation ruled by the Al-Khalifa dynasty.
It repeatedly says it rejects violence, but the authorities in turn blame its supporters for the trouble that has shaken the country.
A month-long protest that erupted on February 14, 2011, was dispersed in a mid-March deadly crackdown helped by security forces from neighbouring Saudi Arabia.
At least 89 people have been killed in Bahrain since the Arab Spring-inspired protests erupted, according to the International Federation for Human Rights.
Demonstrators frequently clash with security forces in Shiite villages outside the capital.
The judicial authorities have stepped up the number of trials of Shiites charged with attacking the police, and protests in Manama have been banned.
King Hamad in August ordered stiffer penalties for "terror acts".
These include a minimum 10-year jail term for an attempted bombing. If such attacks cause casualties, the sentence can be life imprisonment or the death penalty.
Bahrain, a strategic archipelago just across the Gulf from Shiite Iran, is the home base of the US Fifth Fleet and Washington is a long-standing ally of the ruling Sunni dynasty