A protester stands in front of the military in Pearl Square in the Bahraini capital Manama on Wednesday.  [Photo/Agencies]

MANAMA, Bahrain - Soldiers and riot police expelled hundreds of protesters from a landmark square in Bahrain's capital on Wednesday, using tear gas and armored vehicles to try to subdue the growing movement calling for an end to the 200-year-old monarchy. At least six people were killed as clashes flared across the kingdom, according to witnesses and officials.

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The unrest that began last month has shown signs of a sectarian showdown: The country's Sunni leaders are desperate to hold power, and majority Shiites are calling for an end to their dynasty. A Saudi-led force from Gulf allies, fearful for their own regimes and worried about Shiite Iran's growing influence, has grown to more than 1,000 soldiers.

Wednesday's full-scale assault launched at dawn in Pearl Square, the center of the uprising inspired by Arab revolts in Egypt and Tunisia. Hours later, security forces were picking through burned debris and other remains of the protest camp.

In another area of Bahrain, one witness described police in a village "hunting" Shiites in what could be part of a wider campaign of intimidation.

The king's announcement on Tuesday of a three-month emergency rule and the crackdown on Pearl Square sent a message that authorities will strike back with overwhelming force in the strategic island nation, which hosts the US Navy's 5th Fleet.

Security forces barred journalists and others from moving freely around Manama and other areas of the country a day after emergency rule was declared. A 4 am to 4 pm curfew was imposed in most of the country.

Witnesses said at least two protesters were killed when the square was stormed. Officials at Ibn Nafees Hospital said a third protester shot in the back later died from his wounds. The witnesses spoke on condition of anonymity because of fears of reprisals from authorities.

Bahrain state TV also reported that two policemen died when they were hit by a vehicle after protesters were driven out. The Interior Ministry said at least one other police officer was killed, but did not give the cause.

It was unclear whether the offensive included soldiers from other Gulf nations.

But state TV broadcast video showing military vehicles in the square flying Bahrain's red-and-white flag as security officials moved through the wreckage of the encampment, set up at the base of a towering monument to the country's history as a pearl diving center. The video showed the ground littered with debris, including satellite dishes and charred tent poles.

Helicopters crisscrossed over the square, which was cleared by security forces late last month but was later retaken by protesters after a deadly confrontation with army units.

Protesters fled for cover into side streets and security forces blocked main roads into Manama. Mobile phones were apparently jammed in central Manama during the height of the attack, and Internet service remained at a crawl.

AP