Manama, March 13 (IANS) Protesters gathered in Bahrain's capital city Sunday threatened to block access to a key financial hub by forming a human chain, forcing riot police to use teargas and rubber bullets, eyewitnesses said.

Riot police fired "dozens" of tear gas canisters to clear the area around the Bahrain Financial Harbour, a commercial district in Manama where demonstrators have been camped out for more than a week, Al Jazeera reported quoting eyewitnesses.

A number of people were injured in the fresh crackdown Sunday and have been taken away in ambulances, the witnesses said, adding that the police have also encircled Pearl Roundabout, the focal point of the anti-regime protests for nearly a motnth.

During the past couple of months, a wave of unrest have swept through several countries in the Middle East as well as North Africa soon after the mass uprising toppled the long-term regimes in Tunisia and Egypt.

Bahrain's King Hamad bin Isa Al Khalifah has been in power since 2002 when the country was turned into a constitutional monarchy, paving the way for an elected parliament. But the king has been the supreme authority of Shia-dominated Bahrain since 1971.

Manama has been paralysed by protests for weeks, with thousands of people, frustrated by unemployment and economic inequality, camped in the main roundabout of the capital.

The protesters have also staged a number of marches on symbolic targets - the prime minister's office, the foreign ministry, and the state television building, among others.

The sit-in outside the Bahrain Financial Harbour was organised by a group of "youth protesters". The country's six formal opposition parties did not endorse the move.

Bahrain's interior ministry said eight policemen were injured during Sunday's operation to disperse some 350 protesters.

There were "eight injuries among policemen... all were transferred to hospital," the ministry was quoted as saying on its Twitter page.