MANAMA (Reuters) - Tens of thousands of Bahrainis demonstrated outside the capital Manama on Friday to demand urgent political reforms, a year after the Gulf Arab state crushed an uprising, witnesses said.
The protestors began marching along a highway near Manama in response to a call from leading Shi'ite cleric Sheikh Isa Qassim who urged people to renew their calls for greater democracy.
A live blog showed images of the protesters carrying banners denouncing "dictatorship" and demanding the release of detainees.
"We are here for the sake of our just demands that we cannot make concessions over and we stick with them because we have sacrificed for them," Sheikh Isa Qassim said before the march during his weekly sermon in the Shi'ite village of Diraz.
He had promised to personally lead the march, his most high profile action in more than a year of unrest.
A Reuters photographer said the main Budaiya highway in the area of Diraz and Saar west of Manama was packed, just one hour before the protest was set to begin.
"It is the biggest demonstration in the past year. I would say it could be over 100,000," he said.
Majority Shi'ites were in the forefront of last year's protest movement in Bahrain, which erupted in February after uprisings in Egypt and Tunisia.
But the Sunni Muslim ruling Al Khalifa family crushed the protests one month later, imposing a period of martial law and bringing in Saudi and United Arab Emirates troops to restore order.
However the country, where the U.S. Fifth Fleet is based, has remained mired in crisis and Shi'ite youths clash daily with riot police. The unrest has slowed the economy in what was a major tourism and banking hub in the Gulf region.
Tension has risen in recent weeks around the February 14 anniversary of the uprising, with security forces maintaining a tight grip on the traffic intersection that protesters originally occupied.
Pro-government Sunni groups have organized counter rallies, warning the authorities not to enter into a dialogue on reforms that could give the elected parliament legislative clout and the power to form governments.
Those groups look to Sunni power Saudi Arabia as a key ally and demonize the opposition as loyal to Shi'ite Iran, a charge the opposition parties deny. Analysts say Riyadh does not want Bahrain to agree to reforms that empower Shi'ites.
Qassim said Friday's march would show how strong the opposition was.
"The march will either prove your are only an isolated minority making demands, or that the demands are widely popular," he said in his sermon, which was posted on YouTube.
King Hamad appeared to dismiss the opposition last month, saying they were disunited.
(Writing by Andrew Hammond; Editing by Andrew Osborn)