Security forces in Bahrain stormed the headquarters of the country's largest opposition party on Friday – firing tear gas and rubber bullets.
Police also used tear gas to disperse hundreds of opposition supporters attempting to protest elsewhere in the capital.
The raid on the Al Wafeq party compound comes just one month after Bahrain's government admitted "excessive force" had been used to quell the Arab Spring riots staged by the tiny island kingdom's Shiite majority earlier this year.
"I was really shocked to see tear gas and rubber bullets hit our offices," Al Wefaq vice president Sheikh Hussain Al Daihi told Gulf News.
Al Daihi said he was inside the building with foreign journalists when security forces assaulted the building. A 13-year-old girl sustained a serious leg injury during the raid, he added.
The sudden escalation came after authorities banned the weekly Friday protests for the first time since lifting the emergency laws in June.
Bahrain's Interior Ministry issued a statement that "vandals" hurled stones at the police forces behind the office of Al Wefaq. The statement described the shocking raid as "legal procedures."
Defying the protest ban, Shiite clerics on Friday held prayer services on the rubble of mosques that had been bulldozed by authorities earlier this year. It is the first time Shiite clerics have openly participated in anti-government protests.
According to Gulf News at least 38 mosques used by their congregations have been destroyed since the protests began in February.
"We will start a campaign to defend our religious sites and the first such activity starts with a protest at the end of the prayer at Diraz grand mosque," Sheikh Isa Qassim, a senior Shiite cleric in Bahrain, said during his Friday sermon. Diraz is an opposition stronghold northwest of the capital.
"We demand democracy for one people, Sunni and Shiite, and we understand the approach of the government that aims to divide our people. We are the ones who insist on unity - and because of this we are targeted by the government," he said.