Bahraini opposition activists will hold protests throughout the tiny island state on Friday, defying a ban on public gatherings under martial law declared last week. It was not clear who was behind the marches, plans for which were circulated by email and internet. Neither the mainstream Shi'ite Muslim opposition group Wefaq nor the Feb. 14 Youth Movement which led protests at Pearl roundabout that were dispersed by riot police a week ago, were involved. Demonstrators demanding political and constitutional reforms began mass protests against the Al Khalifa ruling family last month, drawing strength from the protest movement that has swept the Arab world in recent months. Last week Bahrain called in troops from its fellow Sunni-ruled neighbours, declared martial law and launched a crackdown that drove the protesters from the streets. Troops and police have fanned out across Bahrain and the government has said security is now the priority. It has banned all marches, but security forces have not broken up the funeral processions of civilians killed in the crackdown -- most of which turn into anti-government protests. Security forces also turned a blind eye last week to a brief protest outside the Drazi mosque after Friday prayers. Thousands turn out at the Drazi mosque each Friday to hear the sermon of Bahrain's top Shi'ite cleric Sheikh Issa Qassim. More than 60 percent of Bahrainis are Shi'ites, and most are campaigning for a constitutional monarchy. Calls by hardliners for the overthrow of the monarchy have alarmed Sunnis, who fear the unrest helps Iran, a Shi'ite state separated from Saudi Arabia and Bahrain by only a short stretch of Gulf waters. WEFAQ DISTANCES ITSELF Western countries appeared to be taking the plans for Friday marches seriously. The British Foreign Office updated its travel advice to warn against travel to Bahrain and to inform Britons going there about the protests. Wefaq, which draws crowds in the tens of thousands when it calls a protest, has distanced itself from the demonstrations on Friday, which were expected to attract mainly young people. "Wefaq affirms the need to protect safety and lives and not to give the killers the opportunity to shed blood," it said on Thursday. Nine demonstrations appear to be planned, across different parts of Bahrain, including one headed toward the airport and one that aims to "liberate" Salmaniya hospital. Security forces raided Salmaniya hospital in the crackdown, removing several tents set up by protesters in previous weeks. Doctors and human rights groups say strict security has hampered medical access and that four medical staff have been arrested. A funeral is also planned on Friday for Hani Abdulaziz, who died after he was hit by rounds of bird shot fired by police near his home in the Shi'ite suburb of Bilad al-Qadim. A protest that had been announced in the Shi'ite suburb of Sanabis on Thursday drew less than 100 people, who did not try to move onto the main road. It ended with police firing a few rounds of tear gas and there appeared to be no casualties. "We're here because we want the end of Al Khalifa," said one protester who gave his name as Ali. "Today we will stay inside Sanabis. Tomorrow, we will go out everywhere.