Security forces have battled demonstrators calling for political reforms and greater freedoms over two days, leading to the deaths of two protesters and the main opposition group vowing to freeze its work in parliament in protest.
In a clear sign of concern over the widening crisis, Bahrain's King Hamad bin Isa Al Khalifa made a rare national TV address, offering condolences for the deaths, pledging an investigation into the killings and promising to push ahead with reforms, which include loosening state controls on the media and Internet.
"We extend our condolences to the parents of the dear sons who died yesterday and today. We pray that they are inspired by the Almighty's patience, solace and tranquility," said the king, who had previously called for an emergency Arab summit to discuss the growing unrest.
As the crowds surged into the Pearl Square in the capital of Manama, security forces appeared to hold back. But key highways were blocked in an apparent attempt to choke off access to the vast traffic circle -- which protesters quickly renamed "Nation's Square" and erected banners such as "Peaceful" that were prominent in Cairo's Tahrir Square, the epicenter of protests there.
The dramatic move Tuesday came just hours after a second protester died in clashes with police in the strategic island kingdom, which is home to the U.S. Navy's 5th Fleet.
Oppositions groups aren't calling for the ruling Sunni monarchy to be ousted, but they do want an end to its grip on key decisions and government posts.
Other demands -- listed on a poster erected in the square -- included the release of all political prisoners, more jobs and housing, an elected Cabinet and the replacement of longtime prime minister, Sheik Khalifa bin Salman Al Khalifa.
The nation's majority Shiites -- about 70 percent of the population of some 500,000-- have long complained of discrimination and being blackballed from important state jobs.
Many in the square waved Bahraini flags and chanted: "No Sunnis, no Shiites. We are all Bahrainis." It also appeared they were planning for the long haul. Some groups carried in tents and sought generators to set up under a nearly 300-foot monument cradling a giant white pearl-shaped ball that symbolizes the country's heritage as a pearl diving center.
Bahrain is one of the most politically volatile nations in the Middle East's wealthiest corner despite having one of the few elected parliaments and some of the most robust civil society groups. A crackdown on perceived dissent last year touched off weeks of riots and clashes in Shiite villages, and an ongoing trial in Bahrain accuses 25 Shiites of plotting against the country's leadership.
A prolonged showdown could draw in the region's two biggest rivals: Saudi Arabia, as close allies of Bahrain's Sunni monarchy, and Iran, whose hard-liners have spoken in support of the nation's Shiite majority.
Bahrain is also an economic weakling compared with the staggering energy riches of Gulf neighbors such as Saudi Arabia and Qatar, which can afford far more generous social benefits. Bahrain's oil reserves are small and its role as the region's international financial hub have been greatly eclipsed by Dubai.
One protester, 24-year-old Hussein Asamahiji, echoed the complaints from Tunisia and Egypt: a lack of jobs and allegations that the ruling elite monopolizes the best opportunities.
"We simply want the chance at a better future," he said. "Egypt showed it's possible."
The bloodshed already has brought sharp denunciations from the largest Shiite political bloc, which suspended its participation in parliament, and could threaten the nation's gradual pro-democracy reforms that have given Shiites a greater political voice.
The second day of turmoil began after police tried to disperse up to 10,000 mourners gathering at a hospital parking lot to begin a funeral procession for Ali Abdulhadi Mushaima, 21, who died in Monday's marches.
Officials at Bahrain's Salmaniya Medical Complex said a 31-year-old man became the second fatality when he died of injuries from birdshot fired during the melee in the hospital's parking lot. The officials spoke on condition of anonymity because they were not allowed to speak to journalists.
After the clash, riot police eventually withdrew and allowed the massive funeral cortege for Mushaima to proceed from the main state-run medical facility in Manama. He was killed Monday during clashes with security forces trying to halt marches to demand greater freedoms and political rights. At least 25 people were injured in the barrage of rubber bullets, birdshot and tear gas, relatives said.
The main Shiite opposition group, Al Wefaq, denounced the "bullying tactics and barbaric policies pursued by the security forces" and said it was suspending its participation in parliament, where it holds 18 of the 40 seats.
The declaration falls short of pulling out the group's lawmakers, which would spark a full-scale political crisis. But Al Wefaq warned that it could take more steps if violence persists against marchers staging the first major rallies in the Gulf since uprisings toppled long-ruling regimes in Tunisia and Egypt.
A statement from Bahrain's interior minister, Lt. Gen. Rashid bin Abdulla Al Khalifa, expressed "sincere condolences and deep sympathy" to Mushaima's family. He expanded on the king's pledge: stressing that the deaths will be investigated and charges would be filed if authorities determined excessive force was used against the protesters.
But that's unlikely to appease the protesters, whose "day of rage" Monday coincided with major anti-government demonstrations in Iran and Yemen.
In the past week, Bahrain's rulers have attempted to defuse calls for reform by promising nearly $2,700 for each family and pledging to loosen state controls on the media.
State media reported that the king telephoned the head of Egypt's ruling military council, Field Marshal Hussein Tantawi, on Tuesday. No further details were given, but Bahrain had earlier appealed for an emergency summit of Arab leaders to discuss the widening protests.
Bahrain's ruling Sunni dynasty also has extremely close ties with the leadership in Saudi Arabia, which is connected to Bahrain by a causeway. Bahrain has given citizenship to Sunnis in Saudi Arabia and across the region to bolster its ranks against the country's Shiite majority.
Bahrain's Sunni leaders point to parliamentary elections as a symbol of political openness. But many Sunnis in Bahrain also are highly suspicious of Shiite activists, claiming they seek to undermine the state and have cultural bonds with Shiite heavyweight Iran.