Bahrain under lockdown as protests surge

Bahrain's ruling monarchy, reinforced by riot police from neighbouring Gulf nations, imposed a nationwide lockdown on Wednesday to suppress the continuing anti-government uprising.

Foreign troops from Sunni Gulf states, including Saudi Arabia and the United Arab Emirates, choked off movement, overran a protesters' camp and ordered a 12-hour curfew in the majority Shia country.

The intervention from neighbouring countries was blasted by protesters as "foreign occupation" and perceived as a pre-emptive measure to prop up Bahrain's leadership against potential influence from Shia-led Iran.

Bahrain's Sunni leadership called the demonstrators "outlaws" in what is beginning to look more like a sectarian showdown, The Associated Press reported.

Obama urges 'maximum restraint'

Witnesses on Wednesday described helicopters firing on homes and doctors treating those wounded in deadly clashes that have left at least five people dead.

U.S. President Barack Obama expressed his concern over the handling of the political unrest, the White House said.

In phone conversations with Bahraini King Hamad bin Isa Al Khalifa and King Abdullah of Saudi Arabia, Obama called for "maximum restraint," White House press secretary Jay Carney told reporters.

Protests began last month as members of the Shia majority called for an end to Bahrain's Sunni leadership and 200-year-old monarchy.

Despite a peaceful start, clashes between security forces — including the contingent from neighbouring Gulf nations — and protesters have turned increasingly violent.

Earlier Wednesday, soldiers and police officers used tear gas and armoured vehicles to force hundreds of protesters from a square in the capital city of Manama.

To help contain the uprising, a force of about 1,000 Saudi troops and other security forces from neighbouring Gulf nations crossed into Bahrain earlier this week.

Bahrain's king declared a three-month state of emergency on Tuesday, giving the military a wider range of options in dealing with protesters.

Wednesday's full-scale assault launched at dawn in Pearl Square, the centre 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.

Concern over Iran's influence

Gulf nations are concerned a Shia uprising indicates that Iran, a Shia-led nation, could exert influence over Bahrain.

Shia Muslims account for more than 70 per cent of Bahrain's population. Protesters in the past month have alleged discrimination and a lack of good job opportunities.

Iran denounced the intervention of Gulf security forces as "unacceptable" Tuesday. Iraqi Shia Muslims also held protests in support of Bahraini protesters Wednesday, burning Saudi King Abdullah in effigy.

Similar rallies were held throughout the region, including in Lebanon where Hezbollah supporters voiced their support for Bahraini protesters.