Troops took control of Manama on Thursday after riot police stormed an anti-government protest camp at dawn and fought demonstrators on the streets, killing four people in Bahrain's worst violence in decades.

Women are overcome by emotion as they wait outside a hospital in Manama, Bahrain's capital, where victims of clashes between anti-government protesters and riot police were being treated on Thursday. [Hassan Ammar / China Daily via Agencies]

Foreign Minister Sheikh Khaled bin Ahmed al-Khalifa said police action pulled Bahrain back from what he called the brink of a sectarian abyss. "So it was a very important step that had to happen. Police took every care possible."

Police cleared the capital's Pearl Square of mainly Shi'ite protesters demanding more say in the Sunni-ruled island kingdom.

"This is an atrocity," Abdul Jalil Khalil, a senior member of the main Shi'ite party Wefaq told Reuters. "Whoever took the decision to attack the protest was aiming to kill."

Health Minister Faisal bin Yaqoob al-Hamer said three people were killed and 231 hurt in the police operation and an opposition MP told Reuters later a fourth person had died of his wounds.

The crackdown by the Bahraini authorities appeared designed to snuff out the protests before they could gather momentum, unlike the sustained unrest that unseated Egypt's Hosni Mubarak.