At least two people are dead and hundreds injured after security forces in Bahrain drove out pro-democracy protesters from the Pearl Roundabout in the capital, Manama.

Helicopters hovered overhead as troops backed by tanks stormed the site – the focal point of weeks-long anti- government protests in the tiny kingdom – early on Wednesday, an Al Jazeera correspondent said.

Multiple explosions were heard and smoke was seen billowing over central Manama.

Our correspondent said the police backed by the military attacked the protesters from all sides and used tear gas canisters to disperse the crowd.

Protesters, intimidated by the sheer numbers of security forces, retreated from the roundabout, he said.

Hospital sources said two protesters had been killed and hundreds of others injured in the offensive. The Reuters news agency said three policemen had also been killed.

He said the situation was very bad and Bahrain was heading towards a disaster.

“The security forces are killing the people, we call upon U.N. to help us,” Aswad said.

State of emergency

The move by the security forces came a day after a state of emergency was declared on the island and at least two people were killed in clashes in the Shia suburb of Sitra outside Manama.

An order by the king “authorised the commander of Bahrain’s defence forces to take all necessary measures to protect the safety of the country and its citizens,” a statement read out on television on Tuesday said.

Hundreds of Saudi-led troops entered Bahrain on Monday as part of a Gulf Co-operation Council (GCC) initiative to help protect government facilities there amid an escalation in the protests against the government.

It was not immediately clear if Wednesday’s security crackdown involved Saudi troops.

Syed Al Alawi, a witness, told Al Jazeera that troops were surrounding the Salmania hospital and not allowing doctors and nurses to enter.

Calling for help, Alawi said: “The GCC troops are for fighting against foreign forces, instead they are targeting the people of Bahrain. What’s our fault? We are asking for our legitimate rights.”

At least 500 protesters have been camping at the Pearl Roundabout in central Manama as part of their demonstration.

And Bahrain’s youth movement has called on Wednesday for a mass demonstration at 3.30pm (1230 GMT) from all Manama suburbs.

The small kingdom with a dominant Shia majority has been swept by protests over the last several weeks. The protesters, alleging discrimination and lack of rights, are seeking political reforms.

The arrival of foreign troops followed a request to members of the GCC from Bahrain.

The United Arab Emirates also sent about 500 police to Bahrain, according to Abdullah bin Zayed Al-Nahyan, the Emirati foreign minister. Qatar, meanwhile, did not rule out the possibility of its troops joining the force.

Sheikh Hamad bin Jassim bin Jabr Al-Thani, the Qatari prime minister and foreign minister, told Al Jazeera: “There are common responsibilities and obligations within the GCC countries.

International concern

The U.S., which counts both Bahrain and Saudi Arabia among its allies, has called for restraint, but has refrained from saying whether it supports the move to deploy troops.

Hillary Clinton, the U.S. secretary of state, who was speaking in Egypt, said Bahrainis must “take steps now” towards a political resolution of the crisis.

Iran, meanwhile, has warned against “foreign interferences”.

“The peaceful demonstrations in Bahrain are among the domestic issues of this country, and creating an atmosphere of fear and using other countries’ military forces to suppress these demands is not the solution,” Hossein Amir Abdollahian, an official from the Iranian foreign ministry, was reported by Iran’s semi-official Fars news agency as saying.

*Published under an agreement with Al-Jazeera.