Ali Ibrahim, deputy chief of medical staff at Salmaniya hospital, said 66 had been admitted suffering wounds from the clash in Pearl Square in the capital. Four were in a critical condition.
The injuries were worse than those seen on Thursday, he said.
Some doctors and medics on emergency medical teams were in tears as they tended to the wounded. X-rays showed bullets still lodged inside victims.
"This is war," said Dr. Bassem Deif, an orthopedic surgeon examining people with bullet-shattered bones.
Protesters described a chaotic scene of tear gas clouds, bullets coming from many directions and people slipping in pools of blood as they sought cover. Some claimed the gunfire came from either helicopters or sniper nests, a day after riot police swept through the protest encampment in Pearl Square, killing at least five people and razing the tents and makeshift shelters that were inspired by the demonstrators in Cairo's Tahrir Square.
An Associated Press cameraman saw army units shooting anti-aircraft weapons, fitted on top of armored personnel carriers, above the protesters, in apparent warning shots and attempts to drive them back from security cordons about 200 meters from the square.
Then the soldiers turned firearms on the crowd, one marcher said. "People started running in all directions and bullets were flying," said Ali Al-Haji, a 27-year-old bank clerk. "I saw people getting shot in the legs, chest, and one man was bleeding from his head."
"My eyes were full of tear gas, there was shooting and there was a lot of panic,» said Mohammed Abdullah, a 37-year-old businessman taking part in the protest.
The clash came hours after funeral mourners and worshippers at Friday prayers called for the toppling of the monarchy in the island nation that is home to the US Navy's 5th Fleet, the centerpiece of the Pentagon's efforts to confront Iranian military influence.
Day by day, the crisis in Bahrain has deepened. The cries against the king and his inner circle — at a mosque and at burials for those killed in Thursday's crushing attack — reflect a sharp escalation of the political uprising, which began with calls for wider democracy.
The mood, however, has turned toward defiance of the entire ruling system after the crackdown on a protest encampment in the capital, Manama, which put the nation under emergency-style footing with military forces in key areas and checkpoints on main roads.
At a mosque in the village of Diraz, an anti-government hotbed, imam Isa Qassim called the Pearl Square assault a "massacre" and thousands of worshippers chanted: "The regime must go."
In a sign of Bahrain's deep divisions, government loyalists filled Manama's Grand Mosque to hear words of support for the monarchy and take part in a post-sermon march protected by security forces. Many arrived with Bahraini flags draped over the traditional white robes worn by Gulf men. Portraits of King Hamad bin Isa Al-Khalifa were distributed.
"We must protect our country," said Adnan Al-Qattan, the man leading prayers. "We are living in dangerous times."
He denounced attempts to "open the doors to evil and foreign influences" — an apparent reference to suspicions that Iran could take advantages of the unrest.
The pro-government gathering had many nonnative Bahrainis, including South Asians and Arabs from around the region.
Outside a village mosque, several thousand mourners gathered to bury three of the men killed in the crackdown. "Our demands were peaceful and simple at first. We wanted the prime minister to step down," Mohamed Ali, a 40-year-old civil servant, said as he choked back tears. "Now the demands are harsher and have reached the pinnacle of the pyramid. We want the whole government to fall."
In another funeral in the village of Karzkan, opposition leaders urged protesters to keep up their fight but not to seek revenge. "We know they have weapons and they are trying to drag us into violence," said Sheikh Ali Salman, the leader of the largest political party, Al-Wefaq, whose 18 lawmakers have resigned in protest from the 40-seat Parliament.
In Geneva, Navi Pillay, the UN High Commissioner for Human Rights, said the response of some governments in the Middle East and Africa to the demands of their people was "illegal and excessively heavy-handed," and she condemned the use of military-grade shotguns by security forces in Bahrain. The European Union and Human Rights Watch urged Bahrain to order security forces to stop attacks on peaceful protesters.
The violence forced the cancellation of a lower-tier open-wheel race in Bahrain for Friday and Saturday, and leaves in doubt the March 13 season-opening Formula One race at the same track. Formula One chief Bernie Ecclestone said he will decide next week whether to proceed with the race. On Friday, he said he hoped the unrest "all blows away" so the event can be run as scheduled.
